Method and apparatus for supplying voltage

Abstract

Voltage waveform (V S1 (t), V F1 A method for generating voltage pulses (V1(t), V2(t)) includes: - providing an optical signal (CLB1) including one or more optical pulse sequences (OPAT1, OPAT2); - distributing the optical pulses (OPAT1) to a plurality of photoelectric conversion units (OEU1, OEU2) via optical waveguides (CWG1, CWG2); - using the photoelectric conversion units (OEU1, OEU2) to convert the optical pulses (OPAT1, OPAT2) into electrical driving current pulses (EPAT1); and - generating voltage pulses (V1(t), V2(t)) by driving a Josephson junction (JJ1) with the electrical driving current pulses (EPAT1).

Description

[Technical Field]

[0001] The present invention relates to providing a voltage waveform. [Background technology]

[0002] The quantized arbitrary voltage waveform may be generated using a conventional Josephson arbitrary waveform synthesizer (JAWS). The conventional Josephson arbitrary waveform synthesizer is driven by an electrical pulse pattern obtained from an electrical pattern generator. The generated voltage level may be accurately determined based on the known repetition rate of the electrical pulses. The repetition rate of the electrical pulses may be traceable to the frequency of an atomic clock. Summary of the Invention [Problem to be solved by the invention]

[0003] An object is to provide a method for generating a voltage waveform. An object is to provide an apparatus for generating a voltage waveform. An object is to provide a voltage source apparatus. An object is to provide a reference voltage. [Means for solving the problem]

[0004] According to one aspect, the voltage waveform (V S1 (t), V F1 The present invention provides a method for generating voltage pulses (V1(t), V2(t)) comprising: - providing an optical signal (CLB1) including one or more optical pulse sequences (OPAT1, OPAT2); - distributing the optical pulses (OPAT1) to a plurality of photoelectric conversion units (OEU1, OEU2) via optical waveguides (CWG1, CWG2); - using the photoelectric conversion units (OEU1, OEU2) to convert the optical pulses (OPAT1, OPAT2) into electrical driving current pulses (EPAT1); and - generating voltage pulses (V1(t), V2(t)) by driving a Josephson junction (JJ1) with the driving current pulses (EPAT1).

[0005] Further aspects are defined in the claims.

[0006] The scope of protection sought for various embodiments of the present invention is defined by the independent claims. To the extent that any embodiments described herein do not fall within the scope of the independent claims, they are to be construed as examples useful for understanding various embodiments of the present invention.

[0007] The voltage source device may include an optical pulse generator that provides optical pulses, an optical feedthrough that directs the optical pulses to the cryogenic chamber, and one or more optical distributors that distribute the optical pulses to multiple optoelectronic converters via optical waveguides. The optoelectronic converters may convert the optical pulses into drive current pulses. The drive current pulses may be transmitted to multiple Josephson junctions via short electrical transmission lines. The Josephson junctions may convert the drive current pulses into voltage pulses such that the integrals of the individual voltage pulses are quantized and the integrals are determined over time. Multiple Josephson junctions may be connected in series to increase the magnitude of the combined voltage pulse.

[0008] The method may include forming a combined voltage signal by combining voltage pulses of multiple Josephson junctions. Combining the voltage pulses of multiple Josephson junctions may, for example, result in an increased voltage level and / or an increased pulse repetition rate of the pulses of the combined voltage signal.

[0009] The synthesized voltage pulse may optionally be low-pass filtered to provide a highly accurate, ripple-free voltage level. In one embodiment, the filtered output voltage may be held constant. The generated voltage pulse may be low-pass filtered to provide a precise reference voltage level.

[0010] The voltage source device may provide selectable and / or arbitrary voltage waveforms, and the device may operate as an optically driven ultrafast cryogenic arbitrary waveform source.

[0011] The apparatus may be arranged to provide a selectable voltage waveform.The apparatus may be arranged to provide a user selectable voltage waveform.The apparatus may be arranged to provide any voltage waveform.

[0012] Distributing the optical pulses to multiple opto-electrical converters may allow the locations of the opto-electrical converters to be selected so that the length of the transmission line is reduced or minimized. Spatially distributing the conversion of optical pulses into drive pulses may allow driving a large number of Josephson junctions and / or substantially avoid the bandwidth limitations of electrical transmission lines.

[0013] The device may include a combination of superconducting, optical, and optoelectronic elements. Optically integrated distributed delivery of ultrafast pulses to Josephson junctions may enable an essentially ideal electrical signal generator, providing near-ideal performance. Output voltage levels may be highly accurate.

[0014] The output voltage level can be accurately determined based on the implementation of voltage standards defined by the International System of Units (SI). The output voltage level can be accurately determined from the pulse repetition rate of the optical pulses. In one embodiment, the pulse repetition rate of the optical pulses can be traceable to the frequency of an atomic clock.

[0015] It can deliver arbitrary waveforms over a wide bandwidth, from 0 Hz to tens of gigahertz. Optical signal delivery at cryogenic temperatures can offer superior energy efficiency by avoiding the fundamental problem of heat conduction in high-frequency electrical cables, described by the Wiedemann-Franz law. In one embodiment, the simplest setup using a single chip and a single optical fiber can already achieve up to 500 independent voltage outputs. This contrasts sharply with state-of-the-art cryogenic signal delivery, which can require numerous electrical coaxial cables to deliver electrical signals to a cryogenic chamber.

[0016] In one embodiment, signal generation can be conveniently controlled with a room temperature device, ie, without the need for cryogenic operational logic.

[0017] In one embodiment, the device may be arranged so that multiple signal outputs may be used to control, for example, a quantum computer.

[0018] In typical quantum electronics applications, where the spacing of quantum mechanical energy levels corresponds to the energy of microwave photons, bandwidths of 10 GHz or more may be required.

[0019] For example, in room temperature measurement applications, a large maximum output voltage may also be used.

[0020] In one embodiment, the waveguide and the optoelectronic converter may be implemented on the same substrate. The voltage source device may operate as an optically integrated quantized arbitrary voltage waveform source.

[0021] The generated voltage levels may be based on macroscopic quantum phenomena, allowing the generated voltage to be determined from the repetition rate of the generated light pulses. The repetition rate of the light pulses may be traceable to, for example, an atomic clock. The generated voltage levels may be traceable to an international standard. In one embodiment, the voltage levels generated by the device may be used as a voltage standard.

[0022] The device may include a plurality of optical waveguides for distributing one or more optical pulse patterns to a plurality of optoelectronic converters. The optoelectronic converters of the device may convert the optical pulses into electrical drive current pulses. The device may include a plurality of Josephson junctions for providing quantized voltage pulses when the Josephson junctions are driven with the electrical drive current pulses. That is, the Josephson junctions may convert the electrical drive current pulses into quantized voltage pulses. The quantized voltage pulses obtained from the Josephson junctions may be combined and optionally filtered to provide an electrical waveform at cryogenic temperatures. Any desired electrical waveform may be provided by selecting one or more optical pulse patterns.

[0023] Guiding the optical pulse sequence through one or more optical waveguides may make it possible to reach high pulse repetition rates of the combined voltage signal and / or reduce losses and dispersion caused by transmitting electrical signals at high frequencies through electrical transmission lines.

[0024] In one embodiment, a first voltage pulse obtained from one or more first Josephson junctions and a second voltage pulse obtained from one or more second Josephson junctions can be combined to form both positive and negative pulses. For example, the positive and negative pulses can be filtered to provide a substantially sinusoidal waveform. For example, the first photoelectric conversion unit can be arranged to provide a drive current pulse having a first polarity for driving one or more first Josephson junctions. The first photoelectric conversion unit can be arranged to provide a drive current pulse having a second, opposite polarity for driving one or more second Josephson junctions.

[0025] In particular, the use of silicon photonics (SiPh) devices and optical-to-electrical converters may make it possible to reach higher frequencies and / or greater voltages by minimizing the role of band-limited electrical transmission lines.

[0026] The device may include an optoelectronic converter for driving a short chain of Josephson junctions. The short chains of Josephson junctions may be connected in series to provide higher voltages and / or improve dynamic range. Small optoelectronic converters may be used to minimize the length of electrical transmission lines.

[0027] Josephson junctions can experience significant electrical losses. Multiple Josephson junctions can be connected in series to form a chain of Josephson junctions, which can be driven with current pulses obtained from an optoelectronic converter. To reduce losses in the Josephson junctions, the length of the chain can be short. The total length of the chain of Josephson junctions connected to the converter can be, for example, less than 100 μm to reduce losses. Shortening the length of the chain can also make it possible to model the electrical behavior of the chain using lumped elements.

[0028] Electrical losses may also occur in the transmission line from the transducer to the Josephson junction. The length of the transmission line from the transducer to the first (or last) Josephson junction in the chain may be shorter than, for example, 3 mm to reduce losses in the transmission line. In particular, the length of the transmission line from the transducer to the first (or last) Josephson junction in the chain may be shorter than, for example, 100 μm.

[0029] Distributing an optical signal to multiple transducers via optical waveguides may allow the locations of the transducers to be selected so that multiple Josephson junctions can be simultaneously driven with synchronized current pulses obtained at high frequencies from the multiple transducers. The number of Josephson junctions may be, for example, 100 or more, 1000 or more, or 10,000 or more, or 100,000 or more. The number of transducers may be, for example, 10 or more, 100 or more, 1000 or more, 10,000 or more, or 100,000 or more. In one embodiment, the transducers and waveguides may be implemented on the same substrate.

[0030] Distributing the optical signal to multiple transducers via optical waveguides may allow the locations of the transducers and Josephson junctions to be selected so that the overall perimeter of each current loop can be shorter than, for example, 100 μm (for each transducer contributing to the output signal). The current loop for the drive current pulse may include a transducer, a first conductive transmission line from the transducer to a chain of Josephson junctions, the chain, and a second conductive transmission line from the chain to the transducer. A short perimeter length of the current loop may minimize losses, provide drive current pulses at a high repetition rate, and / or help avoid unwanted reflections.

[0031] The photoelectric converters can be, for example, plasmonic photodetectors, unit-traveling-carrier photodiodes (UTC-photodiodes), or superconducting nanowire single-photon detectors (SNSPDs).

[0032] An optical signal including one or more optical pulse sequences can be introduced into the cryogenic chamber via an optical feedthrough. The optical pulse sequences can be distributed to multiple optoelectronic converters, for example, by using one or more optical splitters and silicon photonic (SiPh) optical transmission lines. The optical pulse sequences received from the optical feedthrough can be distributed to multiple optical transmission lines, for example, by wavelength division demultiplexing (WDM). The optical pulse sequences can be distributed to multiple optical transmission lines by one or more spectrally selective optical splitters within the cryogenic chamber.

[0033] An optical signal may include multiple optical pulse sequences of different wavelengths, and the different pulse sequences may be demultiplexed from the optical signal onto multiple different optical transmission lines by one or more spectrally selective optical splitters.

[0034] In one embodiment, the optical waveguide and the optoelectronic converter may be implemented on the same substrate. The optoelectronic converter may be located near the Josephson junction, for example, to minimize the length of the electrical transmission line and / or to minimize electrical transmission loss and / or dispersion. The optoelectronic converter may be integrated directly onto the waveguide and located close to the Josephson junction, which may allow for high integration density and performance.

[0035] The bandwidth of the SiPh components and the optoelectronic converters may be, for example, greater than 200 GHz. As a result, the optoelectronic converters may be arranged to provide electrical pulses at a repetition rate that is at least 200 GHz. One or more optoelectronic converters may be arranged to drive a Josephson junction at a pulse frequency of at least 200 GHz. One or more optoelectronic converters may be arranged to drive a chain of Josephson junctions at a pulse frequency of at least 200 GHz.

[0036] One or more optical-to-electrical converters may be arranged to drive a chain of Josephson junctions at frequencies above 200 GHz.

[0037] In one embodiment, the electrical waveform of the photoelectric converter can be low-pass filtered to provide a substantially noise-free output voltage waveform. Furthermore, the instantaneous voltage level of the output voltage waveform can be accurately determined from the repetition rate of the optical pulses directed at the photoelectric converter. The repetition rate of the optical pulses can be accurately known. The repetition rate of the optical pulses can be traceable to an atomic clock.

[0038] Thus, by using sigma-delta modulation and sufficient low-pass filtering, noise-free and calculable voltage signals up to tens of gigahertz can be achieved.

[0039] The generated electrical waveforms may be used, for example, to control quantum computers at cryogenic temperatures.The generated electrical waveforms may be used, for example, to control qubits in quantum computers at cryogenic temperatures.

[0040] The generated electrical waveform may be used, for example, as a voltage reference for calibrating a meter. The generated electrical waveform may be used, for example, as a voltage standard to verify the operation of a meter. The generated electrical waveform may be used for voltage measurement applications at room temperature. The generated electrical waveform may be used for voltage measurement applications at cryogenic temperatures.

[0041] The device can be arranged to provide higher voltage levels and / or higher frequencies compared to common voltage standards based on Josephson junctions.

[0042] In one embodiment, the voltage waveform obtained from the Josephson junction may be coupled outside the cryogenic chamber and used for applications outside the cryogenic chamber. The voltage waveform generated at cryogenic temperatures may be coupled outside the cryogenic chamber and used at normal room temperature.

[0043] A conventional Josephson arbitrary waveform synthesizer (JAWS) is driven by an electrically generated pulse pattern, which produces the absence (0) or presence (1) of electrical current pulses at frequencies traceable to atomic clocks.

[0044] A Josephson junction can be driven with a sequence of electrical drive pulses. This sequence can consist of multiple absent (0) and present (1) current pulses. The symbol "0" can represent a logic level 0, and the symbol "1" can represent a logic level 1. When driving a Josephson junction with electrical pulses, each drive pulse 0 can result in zero voltage, and each drive pulse 1 can produce a voltage pulse across the Josephson junction that has a quantized time integral. The quantized voltage pulse can have positive or negative polarity, depending on the direction of the pulse current through it. The quantized time integral can be equal to an integer multiplied by a magnetic flux quantum. The quantized time integral is typically equal to a single magnetic flux quantum. However, the quantized time integral can also be equal to multiple magnetic flux quanta.

[0045] In one embodiment, the optical pulse pattern generator of the present device may also be arranged to provide multi-level optical pulses, i.e., the amplitude of the optical pulses of the pulse pattern may also be different from zero amplitude and different from full amplitude. Selecting the amplitude of the optical pulses may allow for selecting the Shapiro step index for generating voltage pulses of multiple flux quanta.

[0046] An arbitrary quantized voltage waveform can be generated by providing an optical pulse pattern, converting the optical pulse pattern into an electrical drive pulse using an optical-to-electrical converter, and driving a Josephson junction with the drive pulse to generate a quantized voltage pulse. The arbitrary quantized voltage waveform can be filtered with a low-pass filter to form a filtered output waveform.

[0047] The maximum rate of change and maximum voltage of the filtered output waveform may be limited by the repetition rate of the drive pulses.

[0048] The optical pulses can be converted into electrical driving pulses by a photoelectric converter. The photoelectric converter can be, for example, a uni-traveling-carrier photodiode (UTC-PD). A uni-traveling-carrier photodiode can use only electrons as active carriers. The photoelectric converter can also be, for example, a plasmonic photodetector or a superconducting nanowire single-photon detector (SNSPD). The photoelectric converter can be, for example, a superconducting nanowire detector, which can be configured to detect single photons and / or multiple photons. The superconducting nanowire detector can be a superconducting nanowire single-photon detector or a structurally modified superconducting nanowire single-photon detector. The structurally modified superconducting nanowire single-photon detector can have suitable detection efficiency for detecting multiple photons.

[0049] Superconducting nanowire detectors (SNPDs) can be a variant of the commonly known superconducting nanowire single-photon detectors (SNSPDs), with the difference that SNPDs are not required to be reliable detectors of single photons. For example, the probability of detecting a single photon can be between 1% and 100%. SNPDs can be used to detect optical pulses of, for example, 1, 10, 100, or 1,000 photons. Relaxing the single-photon detection probability criterion can improve device yield and help widen the device bandwidth. UTC photodiodes and plasmonic photodetectors can enable broadband performance of 1 THz or greater. SNPDs can enable good energy efficiency when detecting optical pulses of, for example, 1,000 photons or less. Photoelectric converters can transmit high-frequency signals through nonmetallic optical waveguides, thereby reducing heat flow to cryogenic temperatures.

[0050] As a comparative example, a single UTC photodiode can be arranged to drive all Josephson junctions on a Josephson arbitrary waveform synthesizer chip. Electrical drive pulses can be transmitted to a long array of Josephson junctions via electrical transmission lines. In this comparative example, loss and / or dispersion in the electrical transmission lines can increase with increasing frequency and increasing number of junctions. The increased loss and / or dispersion in the electrical transmission lines can limit both the pulse drive frequency and the number of junctions driven by the transmission lines. The transmission lines can limit the bandwidth for generating arbitrary voltage waveforms.

[0051] The maximum output voltage can be proportional to the drive frequency and the number of junctions. Even if a junction array can be divided into several separate transmission lines using power division (e.g., a Wilkinson power divider), transmission line losses can make it difficult to drive a large number of junctions with a single electrical drive signal. Therefore, transmission line losses can make it difficult to achieve a sufficiently high voltage signal, especially for room temperature applications. Generating multiple flux quantum voltage pulses (Shapiro step index 2, 3, ...) can also double the output voltage, but a higher Shapiro step index requires more precise current pulses and therefore cannot tolerate transmission line attenuation. There can be a trade-off between the drive frequency, the number of Josephson junctions in the array, and the Shapiro step index. The trade-off means that increasing one parameter requires decreasing another. This trade-off generally makes it difficult to increase the output voltage when distributing a single electrical drive signal to a large number of Josephson junctions.

[0052] The use of distributed photoelectric conversion together with optimized electrical transmission lines may allow for an increase in output voltage and / or may increase the bandwidth of the output voltage waveform.

[0053] In one embodiment, waveguides implemented with silicon photonics (SiPh) may enable on-chip transmission and division of ultrafast optical pulse signals with low loss even at high frequencies. Optoelectronic converters may be directly integrated into optical transmission lines to generate electrical drive current pulses. The small footprint of silicon photonics and optoelectronic converters may allow for decentralized optoelectronic conversion, higher component density, a larger total number of Josephson junctions, and shorter maximum transmission line lengths.

[0054] Ultimately, the array of Josephson junctions may be short enough to be considered a lumped element. A first group of Josephson junctions in a first branch may be connected in series with a second group of Josephson junctions in a second branch. Josephson junctions in different branches may be connected in series, for example, by an inductive element.

[0055] By connecting the Josephson junctions of different branches in series with inductive elements, it is possible to substantially prevent crosstalk at high frequencies of the driving pulses while making it possible to sum the output voltages of the branches over a bandwidth of any output voltage waveform.

[0056] In one embodiment, the use of distributed photoelectric conversion may simultaneously enable high drive frequencies, a large number of junctions on a single chip, and a high Shapiro step index.

[0057] The photoelectric converter can be, for example, a plasmonic photodetector, which can be easily incorporated into optical waveguides. In particular, plasmonic photodetectors can be easily integrated with silicon photonic (SiPh) transmission lines.

[0058] The photoelectric converter can also be, for example, a uni-traveling carrier photodiode (UTC).

[0059] The photoelectric converter can be a superconducting nanowire photon detector (SNPD). Generally, the response of an SNPD to an optical pulse consists of a fast rise time (e.g., tens of ps) and a slow falling edge (e.g., 1 ns). By biasing two such SNPDs with opposite currents to deliver electrical pulses of opposite polarity, and by appropriately adjusting the relative optical pulse energies and the relative delays of the optical pulse trains delivered to them, it may be possible to effectively generate pulses with substantially reduced tails. This may enable the use of the SNPD pair to drive a Josephson junction at a higher pulse rate than using a single SNPD.

[0060] Optical waveguides, optical-to-electrical converters, electrical transmission lines, and Josephson junctions can be implemented on the same substrate. These components can be implemented on a single chip. Single-chip implementation can, for example, minimize the length of electrical transmission lines.

[0061] Alternatively, the optical waveguide, the optoelectronic converter, the electrical transmission line, and the Josephson junction can be implemented on two or more different substrates. These components can be implemented on two or more different chips. For example, the optical waveguide and the optoelectronic converter can be implemented on a first substrate, and the Josephson junction can be implemented on a second substrate. An electrical drive signal from the optoelectronic converter of the first chip can be connected to drive the Josephson junction of the second chip. The electrical connection between the electrical transmission line of the optoelectronic converter and the electrical transmission line of the Josephson junction can be formed, for example, by flip-chip bonding.

[0062] A high-frequency optical pulse signal arriving from an optical fiber can be coupled into a silicon photonic transmission line integrated on a silicon chip. Optical power division can be used to distribute the optical pulse pattern signal into multiple branches. Each branch can include an optical-to-electrical converter. Each optical-to-electrical converter can convert the arriving optical pulse into an electrical drive current pulse that is used to drive a Josephson junction.

[0063] When a Josephson junction is driven with an electrical pulse, it outputs a voltage pulse with a quantized time integral. By using delta-sigma conversion and low-pass filtering, any quantized voltage waveform can be generated from the output voltage pulse of the Josephson junction.

[0064] The SiPh waveguide and integrated optoelectronic converter may enable high integration density, increased pulse frequency, and / or a high Shapiro step index. The increased pulse frequency and high Shapiro step index may increase the output voltage. The increased output voltage may be useful, for example, for performing metrology calibration or verification operations at room temperature.

[0065] Increasing the pulse frequency may allow the cutoff frequency of the low pass filter to be increased.

[0066] By distributing optical pulses to multiple photoelectric converters and driving Josephson junctions via only short transmission lines, it may be possible to generate high-frequency arbitrary waveforms at cryogenic temperatures with ultimate precision and extremely low noise. The quantization effect of Josephson junctions may also reduce the electrical noise of the Josephson junction's output pulses.

[0067] High frequency operation, high precision, and low noise can be useful characteristics in many applications, especially when the output waveform is used to drive a quantum computer.

[0068] The device may be energy efficient and may be useful in quantum technology applications.

[0069] The device may provide increased voltage levels that may be useful for room temperature applications.

[0070] In one embodiment, wavelength multiplexing and demultiplexing can be used to drive different branches of a Josephson junction array with different optical pulse sequences. Driving different branches with different optical pulse sequences can be used to increase the effective frequency of delta-sigma conversion even beyond the bandwidth of the optoelectronic converter and Josephson junctions. In particular, the drive current pulses and the resulting quantized voltage pulses can overlap in time, as long as consecutive pulses within the same branch do not overlap.

[0071] In one embodiment, the array of Josephson junctions may be divided into multiple groups, and these groups may have different numbers of Josephson junctions. For example, a first group may have 2 k-1 the second group may have 2 Josephson junctions; k Josephson junctions, and the groups identified by integer index k are k-1 The device may be arranged to drive each group of junctions with a different pulse sequence, to provide greater freedom in selecting the magnitude of the output voltage.

[0072] In one embodiment, the operation of each photoelectric converter can be independently enabled and disabled, for example, by controlling the bias voltage of the photoelectric converter.

[0073] When used in quantum technology applications, one or more optical-to-electrical converters may be selectively enabled or disabled, for example, to improve the dynamic range of the output voltage, to maximize accuracy, and / or to provide the maximum bandwidth of the output voltage waveform.

[0074] In one embodiment, independent groups of junctions may be driven with pulse sequences that provide similar arbitrary waveforms that are time-shifted from one another, which may allow for improved amplitude resolution of the output waveform when groups of junctions are serially connected for output.

[0075] When used at room temperature, distributed photoelectric conversion may allow for an increased total number of Josephson junctions to be driven synchronously. The lengths of the electrical transmission lines between the photoelectric converters and the Josephson junctions may be optimized for the product of the maximum pulse frequency and the number of Josephson junctions. The electrical transmission lines between the photoelectric converters and the Josephson junctions may be of substantially equal length. In one embodiment, one or more photoelectric converters may be selectively enabled or disabled to allow for optimization of operating parameters.

[0076] The apparatus may be used, for example, to provide one or more voltage waveforms to a cryogenic quantum data processor. The apparatus may be used, for example, to scale up quantum computers.

[0077] In the following examples, some variants will be described in more detail with reference to the accompanying drawings. [Brief explanation of the drawings]

[0078] [Figure 1] FIG. 1 shows, by way of example, a voltage source device. [Figure 2] FIG. 2 shows, by way of example, a voltage source arrangement. [Figure 3] FIG. 3 shows, by way of example, a voltage source arrangement. [Figure 4a] FIG. 4a shows, by way of example, an optical pattern generator device. [Figure 4b] FIG. 4b shows an example light pattern generating device. [Figure 5a] FIG. 5a shows, by way of example, the formation of a light pulse that propagates along an arm of a light pattern generating device. [Figure 5b] FIG. 5b shows, as an example, modulating the power of a light pulse propagating along an arm of a light pattern generating device. [Figure 5c]FIG. 5c shows, as an example, how a light pulse pattern is formed by combining modulated pulses from arms of a light pattern generating device. [Figure 6] FIG. 6 shows, as an example, a light pattern generating device that provides light pulses of two different wavelengths. [Figure 7a] FIG. 7a shows, as an example, a photoelectric conversion unit including a bias unit and a plasmonic photodetector. [Figure 7b] Figure 7b shows, as an example, a plasmonic photodetector implemented on a waveguide. [Figure 8] FIG. 8 shows, as an example, multiple converter units mounted on the same substrate. [Figure 9] FIG. 9 shows, by way of example, a light pattern generating device that includes multiple independently controlled outputs. DETAILED DESCRIPTION OF THE INVENTION

[0079] 1, the voltage source device 1000 may include multiple branches B1, B2, B3, and B4. Each branch (B1) may include one or more waveguides (CWG1), one or more photoelectric conversion units (OEU1), and one or more Josephson junctions (JJ1).

[0080] The number of branches may be, for example, 2 or more. The number of branches may be, for example, 4 or more. The number of branches may be, for example, 2 to 10. 6 It can be in the range of

[0081] The apparatus 1000 may include an optical pattern generator OPG1 for providing an optical signal CLB1 including one or more optical pulse sequences OPAT1. The optical signal CLB1 may include one or more optical pulse sequences OPAT1. The one or more optical pulse sequences OPAT1 of the optical signal CLB1 may be formed, for example, according to a primary pattern (e.g., PAT0 in FIG. 5c). The optical pulse sequence OPAT1 may also be referred to as an optical pulse pattern OPAT1. The optical signal CLB1 may include one or more pulse patterns OPAT1, OPAT2. The pulse repetition rate of the optical pulses of the optical signal CLB1 may be, for example, 50 GHz or higher.

[0082] When using a plasmonic photodetector or a UTC photodiode as the transducer, the repetition rate of the optical pulses of the optical pulse sequence can be, for example, 50 GHz or more, and the repetition rate of the optical pulses can be, for example, in the range of 50 GHz to 500 GHz.

[0083] An optical pulse sequence OPAT1 may be guided to an opto-electrical conversion unit OEU1 via a waveguide CWG1. The opto-electrical conversion unit OEU1 may convert the optical pulse sequence OPAT1 into an electric drive current pulse sequence EPAT1. The electric drive current pulse EPAT1 may be transmitted to one or more Josephson junctions JJ1 via a transmission line LIN1. The Josephson junctions JJ1 may be driven by the electric drive current pulse. When driven by the electric drive current pulse EPAT1, the Josephson junctions JJ1 may generate a voltage pulse V1(t).

[0084] The device 1000 may include one or more optical splitters CSPL1 that split an optical pulse (OPAT1) of an optical signal CLB1 to multiple photoelectric conversion units OEU1 and OEU2. The one or more splitters CSPL1 may split the optical pulse (OPAT1) to multiple waveguides CWG1 and CWG2. The split optical pulse (OPAT1) may be guided to the multiple photoelectric conversion units OEU1 and OEU2 via the waveguides CWG1 and CWG2. The device 1000 may include one or more optical splitters CSPL1 that split the optical pulse (OPAT1) to different branches B1, B2, B3, and B4. The one or more optical splitters CSPL1 may be disposed within the cryogenic chamber VES1 so that the optical signal CLB1 may be guided to the cryogenic chamber VES1 through a single optical feedthrough. The optical pulse (OPAT1) may be split to different branches B1, B2, B3, and B4 inside the cryogenic chamber VES1. To also reduce heat conduction and / or radiation through the optical feedthrough OFEED1, one or more optical distributors CSPL1 may be disposed inside the cryogenic chamber VES1. The optical distributor CSPL1 may be arranged to operate at a cryogenic operating temperature (T1).

[0085] The device 100 may include, for example, 1,000 or more Josephson junctions JJ1, 10,000 or more Josephson junctions JJ1, or 100,000 or more Josephson junctions JJ1. Distributing optical pulses to multiple photoelectric conversion units OEU1, OEU2 may facilitate driving a large number of Josephson junctions JJ1 at a high pulse repetition frequency.

[0086] The spatial locations of the photoelectric conversion units (OEC1, OEC2) can be selected, for example, so that the maximum distance (LLIN1) for transmitting the electrical drive current pulse (EPAT1) from each photoelectric conversion unit (OEC1, OEC2) to the Josephson junction (JJ1) is less than 3 mm. A short electrical transmission line (LIN1) can increase the pulse repetition rate and / or reduce loss and / or dispersion.

[0087] The electric driving current pulse (EPAT1) may be transmitted from the photoelectric conversion units (OEC1, OEC2) to the Josephson junction (JJ1) via an electric transmission line (LIN1), and the length (L LIN1 ) may be substantially equal. For example, the deviation of the length of each electrical transmission line (LIN1) from the nominal length (L0) may be, for example, less than 3 mm. The substantially equal lengths of the electrical transmission lines (LIN1) may facilitate synchronization of the operation of Josephson junctions (JJ1) connected to different photoelectric conversion units (OEC1, OEC2). A difference in length of 3 mm may approximately correspond to a 1 ns time delay for a signal propagating at the speed of light.

[0088] A drive current pulse provided by the converter may propagate from the converter to the Josephson junction through a current loop and back to the converter. In one embodiment, the spatial locations of the photoelectric conversion units (OEC1, OEC2) may be selected such that the circumferential length of the converter current loop returning to the converter through the Josephson junction is shorter than, for example, 100 μm.

[0089] An optical signal CLB1 may be guided to an optical-to-electrical converter OEC1 via an optical waveguide WG0. The optical signal may be distributed to a plurality of optical-to-electrical converters OEC1, OEC2 by a plurality of waveguides CWG1, CWG2. In one embodiment, a plurality of optical waveguides CWG1, CWG2 and a plurality of optical-to-electrical converters OEC1, OEC2 may be implemented on the same substrate SUB1 (FIG. 7b).

[0090] The apparatus 1000 may optionally include one or more delay lines CD1, CD2, CD3, CD4 for synchronizing and / or modifying the arrival times of the light pulses arriving at the different photoelectric conversion units OEU1, OEU2.

[0091] One or more Josephson junctions JJ1 in each branch may generate quantized voltage pulses. Several Josephson junctions JJ1 may be connected in series to provide increased voltages.

[0092] One or more Josephson junctions JJ1 in the first branch B1 can generate a voltage pulse V1(t) when driven by a drive current pulse EPAT1 obtained from the photoelectric conversion unit OEU1 in the first branch B1.

[0093] One or more Josephson junctions JJ1 in the second branch B2 can generate a voltage pulse V2(t) when driven by a drive current pulse EPAT1 obtained from the photoelectric conversion unit OEU2 in the second branch B2.

[0094] One or more Josephson junctions JJ1 in the third branch B3 can generate a voltage pulse V3(t) when driven by a drive current pulse EPAT1 obtained from the photoelectric conversion unit OEU3 in the third branch B3.

[0095] One or more Josephson junctions JJ1 in the fourth branch B4 can generate a voltage pulse V4(t) when driven by a drive current pulse EPAT1 obtained from the photoelectric conversion unit OEU4 in the fourth branch B4.

[0096] The voltage pulses of two or more branches (V1(t), V2(t)) form a combined voltage signal V S1 The voltage pulses (V1(t), V2(t)) of two or more branches can be combined to form an increased voltage level. For example, the Josephson junction JJ1 of the first branch B1 can be connected in series with the Josephson junction JJ1 of the second branch B2. The junction JJ1 of the first branch B1 can be connected in series with, for example, one or more inductive components L C can be used to connect in series with the junction JJ1 of the second branch B2. S1 (t) is optionally filtered by a low-pass filter FIL1, and the filtered output signal V F1(t). The apparatus may include output nodes NF1, NF2 for providing a filtered signal. The low-pass filter FIL1 may include, for example, one or more inductive elements L F1 and one or more capacitive elements C F1 It can be implemented by

[0097] The time integral of each voltage pulse V1(t) across the Josephson junction JJ1 can be quantized according to the well-known quantum mechanical Josephson effect. The time integral of each voltage pulse V1(t) across the Josephson junction JJ1 may be just equal to an integer multiple of the magnetic flux quantum h / (2e), where h is Planck's constant and e is the elementary charge. When the Josephson junction is driven with current pulses of known repetition rate f, the average voltage across the junction is equal to h / (2e) multiplied by an integer multiple of the repetition rate.

[0098] As a result, the average value (V1(t)) of the voltage pulse of the Josephson junction JJ1 can be accurately calculated from the repetition rate of the drive current pulse EPAT1, which may be equal to the repetition rate of the optical pulse OPAT1.

[0099] The repetition rate of the optical pulses OPAT1 may be controlled or measured by the clock CLK1 used. The repetition rate of the optical pulses OPAT1 may be precisely known and may be traceable to an international frequency standard.

[0100] The filtered output signal V F1 The voltage levels of the filtered output signal V(t) can be accurately determined from the quantized time integrals of the voltage pulses (V1(t), V2(t), V3(t), V4(t)). F1 The voltage level of (t) can be accurately determined from the repetition rate of the optical pulses directed into the different branches of the device 1000. The filtered output signal V F1The voltage level of (t) may be traceable to the frequency of an atomic clock, which may be, for example, a cesium atomic clock.

[0101] In one embodiment, the filtered output signal V F1 (t) can be used as a high-precision voltage standard. The method involves deriving the filtered output signal V from the repetition rate(s) of the optical pulses of the optical signal CLB1. F1 (t)。 (t) may include determining the voltage level.

[0102] The photoelectric conversion unit (OEU1) and the Josephson junction (JJ1) may be arranged to operate at a cryogenic temperature (T1). The operating temperature of the photoelectric conversion unit (OEU1) and the Josephson junction (JJ1) may be, for example, lower than 20K, lower than 5K, or even lower than 1K.

[0103] The photoelectric conversion unit (OEU1) and the Josephson junction (JJ1) may be arranged to operate inside a cryogenic chamber VES1. The apparatus 1000 may include the cryogenic chamber VES1. The apparatus 1000 may include a cooling system SYS1 that provides a cryogenic operating temperature (T1) for the photoelectric conversion unit (OEU1) and the Josephson junction (JJ1). T0 may indicate ambient temperature.

[0104] The cryogenic temperature T1 may be lower than 5 K, for example. For example, the upper temperature limit of liquid helium is 4.2 K, and it is also possible to achieve a cryogenic temperature T1 lower than 5 K by using a cooling system SYS1 that utilizes liquid helium. In more demanding applications, the cooling system SYS1 may be arranged to keep the cryogenic temperature T1 lower than, for example, 1 K. The difference between the ambient temperature T0 and the internal cryogenic temperature T1 may be greater than, for example, 100 K. The ambient temperature T0 may be approximately equal to, for example, a normal room temperature of 25° C. (298 K).

[0105] The system 1000 may include one or more optical feedthroughs OFEED1 for directing the optical signal CLB1 to the cryogenic chamber VES1.

[0106] For example, optical signal CLB1 may be guided into cryogenic chamber VES1 via a single optical feedthrough OFEED1 and via a single optical waveguide WG0.

[0107] The use of the optical feedthrough OFEED1 may facilitate maintaining the cryogenic temperature of the cryostat VES1. Using the optical feedthrough OFEED1 to direct an optical signal to the cryostat VES1 may significantly reduce the heat power transferred to the cryostat VES1 through the feedthrough OFEED1 compared to a situation in which an electrical signal having the same pulse rate is directed to the cryostat VES1 through an electrical feedthrough.

[0108] Referring to FIG. 2 , the multiple Josephson junctions JJ1 may be divided into two or more groups such that the number of first Josephson junctions JJ1 in a first group is different from the number of second Josephson junctions JJ1 in a second group. The first Josephson junctions JJ1 in the first group may be connected in series with the second Josephson junctions JJ1 in the second group. The operation of the Josephson junctions JJ1 in different groups may be independently enabled and disabled by one or more control signals. Independent control of the different groups may improve the dynamic range of the generated voltage. Independent control of the different groups may enable selection of an optimal subset of active branches (B1, B2, B3, B4) to generate a desired voltage level and / or to generate a desired voltage waveform.

[0109] For example, to enable and disable the operation of the first photoelectric conversion unit OEU1 of the first branch B1, a control signal S C1 For example, the first control signal S C1may be arranged to enable and disable the operation of a bias unit (BIAS1) of the first photoelectric conversion unit OEC1. Enabling the operation of the first photoelectric conversion unit OEU1 may enable the operation of the Josephson junction JJ1 of the first branch B1, and disabling the operation of the first photoelectric conversion unit OEU1 may disable the operation of the Josephson junction JJ1 of the first branch B1, respectively.

[0110] Similarly, the operation of Josephson junctions JJ1 in other branches B2, B3, and B4 is controlled by the control signal S C2 , S C3 , S C4 It can be enabled or disabled by

[0111] One or more control signals S C1 , S C2 may enable selecting active photoelectric converters capable of converting optical pulses into electrical drive current pulses. One or more control signals may enable selecting disabled photoelectric converters, respectively. A first control signal may be arranged to enable and disable operation of a first group of photoelectric converters, and a second control signal may be arranged to enable and disable operation of a second group of photoelectric converters.

[0112] First control signal S C1 may enable enabling and disabling the operation of the Josephson junction JJ1 in the first branch B1 of the device 1000 by controlling the operation of one or more photoelectric converters OEC1 in the first branch B1. C2 may enable and disable the operation of the Josephson junction JJ1 in the second branch B2 of the device 1000 by controlling the operation of one or more photoelectric converters OEC2 in the second branch B2. The Josephson junction JJ1 in the first branch B1 of the device 1000 may be connected in series with the Josephson junction JJ1 in the second branch B2 of the device 1000, for example, to improve the signal dynamic range.

[0113] In one embodiment, the plurality of Josephson junctions JJ1 may be divided into two or more groups such that the number of first Josephson junctions JJ1 in a first group is different from the number of second Josephson junctions JJ1 in a second group.

[0114] For example, one group may include only one Josephson junction JJ1. For example, the first group may include two Josephson junctions JJ1. For example, the second group may include four Josephson junctions JJ1.

[0115] In one embodiment, the array of Josephson junctions may be divided into multiple groups, and these groups may have different numbers of Josephson junctions. For example, a first group may have 2 1 the second group may have 2 Josephson junctions; 2 Josephson junctions, and the group denoted by an integer index k is 2 k The Josephson junction may be:

[0116] In one embodiment, the operation of each group of Josephson junctions may be enabled and disabled independently, such as to provide greater freedom in selecting the magnitude of the output voltage.

[0117] The Josephson junctions JJ1 may be divided into two or more groups, a first group including first Josephson junctions JJ1 connected in series, a second group including second Josephson junctions JJ1 connected in series, the first Josephson junctions JJ1 being connected in series to the second Josephson junctions JJ1, the number of Josephson junctions JJ1 in the first group being different from the number of Josephson junctions JJ1 in the second group, and the method includes enabling and disabling the operation of the Josephson junctions JJ1 in the first group in a situation where the operation of the Josephson junctions JJ1 in the second group is enabled.

[0118] In one embodiment, the apparatus 1000 can be arranged to drive each group of junctions with a different pulse sequence, eg, to provide greater flexibility in selecting the magnitude of the output voltage.

[0119] 3, an optical signal CLB1 may include two or more optical pulse sequences OPAT1 and OPAT2 having different wavelengths λ1 and λ2. The optical pulses OPAT1 and OPAT2 may be guided to one or more spectrally selective splitters CDIC1 via a single waveguide WG0. The one or more spectrally selective splitters CDIC1 may spectrally selectively split the optical pulses to different photoelectric conversion units OEU1 and OEU2.

[0120] The optical signal CLB1 may include a first optical pulse sequence OPAT1 at a first wavelength λ1 and a second optical pulse sequence OPAT2 at a second, different wavelength λ2. The method may include spectrally separating the first optical pulse sequence OPAT1 from the optical signal CLB1 and directing the separated first optical pulse sequence OPAT1 to one or more first photoelectric conversion units OEU1, and the method may include directing the second optical pulse sequence OPAT2 to one or more second photoelectric conversion units OEU2.

[0121] Spectrally separating the optical pulses of different wavelengths λ1, λ2 into different branches B1, B2 may allow for independent control of the different branches B1, B2.

[0122] By spectrally separating the optical pulses of different wavelengths λ1, λ2 into different branches B1, B2, the dynamic range can be improved.

[0123] Spectrally separating the optical pulses of different wavelengths λ1, λ2 into different branches B1, B2 may allow for selecting an optimal subset of branches B1, B2 to generate a desired voltage waveform.

[0124] In one embodiment, the arrival times of the light pulses at the different photoelectric conversion units OEU1 and OEU2 are determined by the composite voltage signal V S1 To increase the pulse repetition rate of (t), the pulses may be interlaced.

[0125] The interlaced arrival times of the light pulses result in a composite voltage signal V S1 In an application where (t) is filtered by a low-pass filter FIL1, it may be possible to increase the cut-off frequency of the low-pass filter FIL1.

[0126] Referring to FIGS. 4a and 4b, the light pattern generating device OPG1 may, for example, generate the light pulse pattern OPAT1 by a method, which includes: - distributing a primary pulse (LB00) into a plurality of secondary pulses (LB0); - directing the secondary pulse (LB0) to propagate along different optical branches (A1, A2, A3, A4); forming a modulated optical signal (LB1) by modulating secondary pulses (LB0) propagating along different optical branches (A1, A2, A3, A4); -Different delay times (Δt D1 , Δt D2 , Δt D3 , Δt D4 ) delaying the modulated optical signal (LB1) or delaying the secondary pulse (LB0); and - forming an optical signal (LB2) by combining delayed modulated signals (LB1) from different optical branches (A1, A2, A3, A4);

[0127] The primary pulse (LB00) may be, for example, a laser pulse obtained from a laser source. The optical pattern generating device OPG1 may include, for example, a laser source for supplying the laser pulse.

[0128] The optical pattern generating device OPG1 may include one or more distributors SPL1 that distribute the primary pulse (LB00) to form a plurality of secondary pulses (LB0). The one or more distributors SPL1 may form the secondary pulses (LB0) by distributing the light of the primary pulse (LB00) to branches (A1, A2, A3, A4) of the generating device OPG1.

[0129] The optical pattern generating device OPG1 may include an array MAR1 of modulators MOD1, MOD2, MOD3, MOD4 for forming a modulated optical signal (LB1) from the secondary pulses (LB0). The modulators may be, for example, Mach-Zehnder modulators.

[0130] The optical pattern generating device OPG1 generates different delay times (Δt D1 , Δt D2 , Δt D3 , Δt D4 ) The delay lines may be implemented, for example, by waveguides of different lengths.

[0131] The optical pattern generating device OPG1 may include one or more combiners CMB1 that combine delayed modulated signals (LB1) from different optical branches (A1, A2, A3, A4).

[0132] Each branch (A1, A2, A3, A4) may include an independently controllable modulator (MOD1, MOD2, MOD3, MOD4) and a delay line D1, D2, D3, D4.

[0133] The output OUT1 of the combiner CMB1 may provide an optical signal LB2 constituting any desired optical pulse pattern PAT1. The maximum pulse repetition rate of the optical pulse pattern PAT1 at the combiner output OUT1 may be equal to M·f0, where f0 denotes the repetition rate of the primary pulses (LB00) and M denotes the number of branches (A1, A2, A3, A4) feeding the combiner CMB1. The number of branches M may be, for example, in the range of 4 to 1024.

[0134] In one embodiment, the optical output signal LB2 may be coupled as an input signal CLB1 to an optical feedthrough OFEED1 of the cryogenic chamber VES1.

[0135] The optical pattern generating device OPG1 may optionally include one or more optical amplifiers (AMP3) for amplifying the optical power of the optical pulses. In one embodiment, an optical signal obtained from the output (OUT3) of the optical amplifier (AMP3) may be coupled as an input signal CLB1 to the optical feedthrough OFEED1 of the cryogenic chamber VES1.

[0136] Delay lines (D1, D2, D3, D4) may be placed between the distributor SPL1 and the modulators (MOD1, MOD2, MOD3, MOD4).

[0137] In one embodiment, the timing of the primary pulse (LB00) is determined by, for example, the synchronization signal S SYNC can be used to synchronize with clock CLK1.

[0138] In one embodiment, the timing of the primary pulse (LB00) may even be traceable to the time of the atomic clock (CLK1).

[0139] The state of each modulator can be set to a pass state or a blocking state. In the blocking state, the modulator can prevent the propagation of an optical pulse. In the pass state, the modulator can allow the propagation of an optical pulse. As a result, in the pass state, the modulator can provide an existing optical pulse. In the blocking state, the modulator can provide a missing optical pulse.

[0140] The optical pattern generating device OPG1 may include a control unit PG0 for controlling the states of the modulators. The optical pattern generating device OPG1 may include a memory MEM1 for storing a primary pattern PAT0. The control unit PG0 controls the optical pattern generating device OPG1 according to the primary pattern PAT0 and according to the timing signal S SYNC The optical pattern generating device OPG1 may include one or more data processors PROC1 that provide control signals b1, b2, b3, b4 for changing the states of the modulators in accordance with the control signals b1, b2, b3, b4. The optical pattern generating device OPG1 may optionally include a drive unit DRV1 that amplifies the control signals b1, b2, b3, b4 as needed. For example, the drive unit DRV1 may provide high-voltage drive signals S1, S2, S3, S4 to the modulators based on the control signals b1, b2, b3, b4 as needed.

[0141] Each modulator may be modulated at a frequency less than or equal to the repetition rate of the primary light pulses LB00.

[0142] The maximum modulation frequency of each modulator (MOD1, MOD2, MOD3, MOD4) may be equal to the repetition rate f0 of the primary pulse (LB00). The repetition rate f0 of the primary pulse (LB00) may be, for example, less than 10 GHz, or even less than 1 GHz. Even when generating an arbitrary waveform, it is not necessary to change the state of each modulator faster than f0. As a result, the maximum pulse repetition rate of the optical pulse pattern PAT1 may be higher than the maximum modulation rate of each modulator.

[0143] Referring to FIG. 5a, the light source LS1 of the optical pattern generating device OPG1 has a repetition rate f0 (=1 / T 00) may provide a primary light pulse sequence LB00. The distributor (SPL1) may form multiple secondary pulses LB0 from the single primary light pulse LB00, and the distributor (SPL1) may direct the secondary pulses LB0 to propagate along different branches (A1, A2, A3, A4) of the optical pattern generating device OPG1. The repetition rate of the secondary pulses in each branch may be equal to the repetition rate (f0) of the primary light pulse LB00.

[0144] T 00 is a series of primary pulses LB00 k , LB00 k+1 The pulse repetition frequency f0 of the primary pulse LB00 is 1 / T 00 It can be equal to w 00 may indicate the time width of the primary pulse LB00. T0 may indicate the time width of the consecutive secondary pulses LB0 k , LB0 k+1 The pulse repetition frequency f0 of the secondary pulse LB0 may be equal to 1 / T0. The pulse repetition frequency of the secondary pulse LB0 may be equal to the pulse repetition frequency f0 of the primary pulse LB00. w0 may indicate the time width of the secondary pulse LB0. The symbol P may indicate the optical power of the pulse. d 00 may represent a propagation delay. The primary pulse LB00 may be distributed to the branches of the optical pattern generating device OPG1 to form the secondary pulse LB0.

[0145] 5b and 5c, the modulator (MOD) of each branch (A) may form a modulated optical signal from the secondary pulses LB0 arriving at the modulator (MOD) by passing or blocking the pulses. The state of each modulator may be controlled according to a primary pattern PAT0. The primary pattern PAT0 may be read, for example, from a memory MEM1. The primary pattern PAT0 may be read, for example, from a computer-readable memory MEM1 of the control unit PG0 of the optical pattern generating device OPG1. The primary pattern PAT0 may be, for example, a value b k,1 , bk,2 , b k,3 , b k,4 , b k+1,1 , b k+1,2 , b k+1,3 , b k+1,4 The control signals S1, S2, S3, S4 can be defined by a sequence of the value b k,1 , b k,2 , b k,3 , b k,4 , b k+1,1 , b k+1,2 , b k+1,3 , b k+1,4 The state of each modulator can be set to a pass state or a blocking state according to control signals S1, S2, S3, and S4. C may indicate the time lead between reading the value of the primary pattern PAT0 and the arrival of the optical pulse at the modulator.

[0146] In one embodiment, the primary pattern PAT0 may be obtained, for example, from a data communication path. In one embodiment, the primary pattern PAT0 may be determined according to data obtained from the data communication path.

[0147] Referring to FIG. 5c, the secondary pulse LB0 or ​​modulated signal propagating along each branch of the optical pattern generating device OPG1 has a different delay time Δt D1 , Δt D2 , Δt D3 , Δt D4 The delayed optical signals from the different branches may be combined to form an optical pulse pattern PAT1. The maximum repetition rate of the pulses of the pulse pattern PAT1 may be equal to M·f0, where M denotes the number of branches combined at the output and f0 denotes the repetition rate of the primary pulse LB00. d p may denote a propagation delay; w2 may denote an optical pulse width of the optical pulse pattern; and g3 may denote a period between successive pulses of the optical pulse pattern.

[0148] 6, the light pattern generating device OPG1 may be arranged to provide a first light pulse pattern PAT1 at a first wavelength λ1 and a second light pulse pattern PAT2 at a second wavelength λ2. The second light pulse pattern PAT2 may be synchronized and / or interlaced with the first light pulse pattern PAT1.

[0149] The generating device OPG1 may include a first light source LS1 for providing primary light pulses LB00 at a first wavelength λ1 and a second light source LS2 for providing primary light pulses LB00 at a second wavelength λ2. The operation of the second light source LS1 is controlled by a synchronization signal S SYNC can be used to synchronize the operation of the first light source LS1.

[0150] The first splitter SPL1 may form secondary light pulses LB0 from the primary pulses LB00 of the first light source LS1 and may direct the secondary light pulses LB0 to propagate along the first group of branches. The secondary pulses propagating along each branch of the first group may be modulated, delayed, and combined to form the first light pulse pattern PAT1.

[0151] The second splitter SPL2 may form secondary optical pulses LB0 from the primary pulses LB00 of the second light source LS2 and may guide the secondary optical pulses LB0 to propagate along the second group of branches. The secondary pulses propagating along each branch of the second group may be modulated, delayed, and combined to form a second optical pulse pattern PAT2. The optical pulse patterns PAT1 and PAT2 may be combined to form a wavelength-multiplexed optical signal CLB1 including the optical pulse patterns PAT1 and PAT2. The optical pattern generating device OPG1 may optionally include one or more optical amplifiers to amplify the wavelength-multiplexed optical signal CLB1.

[0152] The second splitter SPL2 may form secondary light pulses LB0 from the primary pulses LB00 of the second light source LS2. The secondary pulses propagating along each branch of the second group may be modulated by a second array of modulators MAR2. The second array of delay lines DAR2 may provide different delay times for the different branches. The output OUT2 of the second combiner CMB2 may provide an optical signal by combining the light pulses from the different branches. The generating device OPG1 may include a delay line D for delaying the second pulse pattern PAT2 with respect to the first pulse pattern PAT1. C2 Optionally, a delay line D C2 may have an output OUT2D for providing a delayed pulse pattern.

[0153] By distributing the optical pulses to multiple branches of the optical pattern generating device OPG1 and combining the modulated delay signals from different branches of the optical pattern generating device OPG1, it is possible to provide highly accurate stable optical pulses at a high repetition rate. Furthermore, the repetition rate of the optical pulses can be made highly accurate.

[0154] In one embodiment, the optical pattern generating device OPG1 may also be implemented by obtaining an electrical signal, for example, from an electrical arbitrary waveform generator, and converting the electrical signal into a sequence of optical pulses, for example, by modulating the output of a laser. For example, the output of a laser diode may be modulated according to the electrical signal generated by the electrical arbitrary waveform generator. In this case, the characteristics of the optical pulses may be limited by the characteristics of the electrical signal from the electrical arbitrary waveform generator.

[0155] 7a, each photoelectric conversion unit OEU1 may include one or more photoelectric converters OEC1, which may be, for example, plasmonic photodetectors.

[0156] The photoelectric conversion unit OEU1 may include a bias unit BIAS1 that supplies a bias voltage to the photoelectric converter OEC1. The bias unit BIAS1 may supply a bias voltage for the plasmonic photodetector. The bias unit BIAS1 may be connected in series with connection nodes ND1 and ND2 of the photoelectric converter OEC1.

[0157] The optical pulses may temporarily increase the conductivity between nodes ND1 and ND2 such that conversion unit OEU1 may generate drive current pulses i1(t). The photoelectric conversion unit OEU1 may convert the optical pulse sequence OPAT1 into a drive current pulse sequence EPAT1.

[0158] Each of the photoelectric converters OEC1 and OEC2 may be optionally mounted on an optical waveguide CWG1 or CWG2, and the optical waveguides (CWG1 and CWG2) may be, for example, silicon waveguides.

[0159] FIG. 7b shows, by way of example, a plasmonic photodetector OEC1 implemented on an optical waveguide CWG1. The plasmonic photodetector OEC1 may include metal structures AU1 and AU2 defining a plasmonic gap SPC1. The plasmonic gap SPC1 may be at least partially filled with a semiconductor material GE1, such as germanium. Light of the optical signal CLB1 may be coupled from the waveguide CWG1 to the plasmonic gap SPC1 by evanescent coupling to effectively interact with the semiconductor material GE1. The metal structures AU1 and AU2 may include or consist of, for example, gold. The metal structures AU1 and AU2 may be arranged to operate as output nodes ND1 and ND2 of the plasmonic photodetector OEC1. The waveguide CWG1 may be implemented on a substrate SUB1. The waveguide CWG1 may be, for example, a silicon waveguide implemented on the substrate SUB1.

[0160] Plasmonic photodetectors (OECs) can include one or more metal structures for confining light by coupling electromagnetic waves to charge carrier vibrations at the surface of the metal. The wavelength of the vibrations can be smaller than the corresponding wavelength in a vacuum. As a result, the interaction between light and matter in the subwavelength region can enable the creation of compact, high-speed photodetectors.

[0161] Plasmonic photodetectors or superconducting nanowire single photon detectors (SNSPDs) may allow for changing the polarity of the output current pulses, for example, by changing the polarity of the bias power supply.

[0162] Referring to FIG. 8 , multiple waveguides CWG1, CWG2, ... CWG30 and multiple converter units OEU1, OEU2, ... OEU30 may be implemented on the same substrate SUB1. The apparatus 1000 may include an integrated module CHIP1 including multiple optoelectronic converters and multiple waveguides for distributing one or more optical pulse patterns to the optoelectronic converters. One or more optical pulse patterns OPAT1 of an optical signal CLB1 may be distributed to the converter units OEU1, OEU2 via one or more optical splitters CSPL1 and multiple waveguides CWG1. The optical distribution of the one or more optical pulse patterns OPAT1 may enable selecting spatial positions POS1 of the converter units OEU1, OEU2 so that the length of the electrical transmission line LIN1 may be reduced or minimized. As a result, distributing the optical pulse pattern OPAT1 via multiple waveguides may enable a high repetition rate of the drive current pulses and / or reduce losses.

[0163] The position of each transducer unit may be specified, for example, by coordinates (x, y). SX, SY, and SZ may indicate orthogonal directions. For example, the position POS1 of transducer unit OEU1 may be specified by coordinates (x1, y1). For example, the position POS30 of transducer unit OEU30 may be specified by coordinates (x 30 ,y 30 )

[0164] A plurality of Josephson junctions may be connected in series to form a chain CHAIN1. An optoelectronic converter may be arranged to provide drive current pulses to the chain CHAIN1 of Josephson junctions JJ1. The number of Josephson junctions JJ1 in the chain CHAIN1 may be, for example, in the range of 4 to 128. One or more converters of the device may also be arranged to drive fewer than four Josephson junctions JJ1.

[0165] Multiple chains (CHAIN1) of Josephson junctions (JJ1) are connected in series to generate a composite voltage signal (V S1 (t)). Each chain (CHAIN1) may include at least four Josephson junctions (JJ1) connected in series. All Josephson junctions (JJ1) of each contributing chain (CHAIN1) may be driven by an electric driving current pulse (EPAT1) obtained from an opto-electric conversion unit (OEC1) connected to the chain (CHAIN1). The maximum length of each contributing chain (CHAIN1) may be, for example, less than 100 μm. The chain length may refer to the length of the electric path from the first Josephson junction (JJ1) to the last Josephson junction (JJ1) of the chain. The contributing chains are driven by a composite voltage signal (V S1 It can be a chain that contributes to (t).

[0166] Referring to FIG. 9, the generating device OPG1 may include a plurality of photoelectric conversion units OEU1, OEU2, OEU3, OEU4, Josephson junctions JJ1, and a plurality of filters FIL1, which generate a plurality of independently controllable output signals V F1 , V F2 , V F3 , V F4 The first output voltage signal V F1 can be formed by converting the first optical pulse OPAT1 into an electrical driving current pulse EPAT1. The second output voltage signal V F2can be formed by converting the second optical pulse OPAT1 into an electrical drive current pulse EPAT2. A first voltage pulse V1(t) can be generated by driving a Josephson junction (JJ1) with the electrical drive current pulse (EPAT1). A second voltage pulse V2(t) can be generated by driving a Josephson junction (JJ1) with the electrical drive current pulse (EPAT2). A first filtered signal V F1 By filtering the second voltage pulse V2(t) with a second filter (FIL1), a second filtered signal V F2 The generating device OPG1 may include a plurality of outputs OUT1, OUT2, OUT3, OUT4 for providing a plurality of different output signals. The generating device OPG1 may generate a first output signal V from a first output OUT1. F1 The generating device OPG1 may be arranged to provide a second output signal V from a second output OUT2. F2 can be arranged to provide.

[0167] The method includes generating a first output signal (V(t)) from a voltage pulse (V(t)) generated by one or more first Josephson junctions (JJ1). F1 ), and generating a second different output signal (V from the voltage pulse (V(t)) generated by one or more second Josephson junctions (JJ1). F2 and forming a

[0168] In one embodiment, the Josephson junction (JJ1) and the optical-to-electrical converters (OEC1, OEC2) are implemented on a first substrate, and the optical waveguides (CWG1, CWG2) are implemented on a second, different substrate.

[0169] It will be apparent to those skilled in the art that modifications and variations of the devices and methods according to the present invention are perceptible. The figures are schematic. The specific embodiments described above with reference to the accompanying drawings are illustrative only and are not intended to limit the scope of the invention as defined by the appended claims.

Claims

1. Voltage waveform (V Ｓ１ (t), V Ｆ１ (t)), comprising the steps of: - different wavelengths (λ １ , λ ２ providing an optical signal (CLB1) including a plurality of optical pulse sequences (OPAT1, OPAT2); - distributing a plurality of optical pulse sequences (OPAT1, OPAT2) to a plurality of photoelectric conversion units (OEU1, OEU2) via optical waveguides (CWG1, CWG2) by wavelength division demultiplexing (WDM); - using photoelectric conversion units (OEU1, OEU2) to convert a plurality of optical pulse sequences (OPAT1, OPAT2) into electrical driving current pulses (EPAT1, EPAT2); - A voltage pulse (V １ (t), V ２ (t) Including, The method, wherein the voltage waveforms (V S1 (t), V F1 (t)) are generated based on the voltage pulses (V 1 (t), V 2 (t)).

2. Voltage pulse (V １ (t), V ２ (t)) to generate a composite voltage signal (V Ｓ１ 10. The method of claim 1, comprising forming (t).

3. A voltage pulse (V) generated by one or more first Josephson junctions (JJ1) １ (t)) to the first output signal (V Ｆ１ ) and generating a voltage pulse (V) generated by one or more second Josephson junctions (JJ1). ２ (t)) to generate a second different output signal (V Ｆ２ and forming a crystalline silicon layer.

4. A plurality of chains (CHAIN1) of Josephson junctions (JJ1) generate a composite voltage signal (V Ｓ１ (t)), each chain (CHAIN1) includes at least four Josephson junctions (JJ1) connected in series, and all Josephson junctions (JJ1) of each contributing chain (CHAIN1) are driven by an electric driving current pulse (EPAT1) obtained from an opto-electric conversion unit (OEU1) connected to said chain (CHAIN1), and the maximum length of each contributing chain (CHAIN1) is shorter than 100 μm, and the contributing chains are driven by a composite voltage signal (V Ｓ１ The method according to any one of claims 1 to 3, wherein the chain contributes to (t).

5. The electric drive current pulse (EPAT1) is transmitted from the photoelectric conversion units (OEU1, OEU2) to the Josephson junction (JJ1) through the electric transmission line (LIN1). ０ The length (L) of the electrical transmission line (LIN1) is determined so that the deviation from ＬＩＮ１ 5. The method of claim 1, wherein the ratios of the first to the second carbon atoms are substantially equal.

6. The composite voltage signal (V Ｓ１ (t)) with a low-pass filter (FIL1) to obtain a filtered voltage waveform (V Ｆ１ 10. The method of claim 2 or 4, comprising forming (t)).

7. The method according to any one of claims 1 to 6, wherein each photoelectric conversion unit (OEU1, OEU2) comprises one or more photoelectric converters (OEC1, OEC2), and the optical waveguides (CWG1, CWG2) and the photoelectric converters (OEC1, OEC2) are mounted on the same substrate (SUB1).

8. The method according to any one of claims 1 to 7, wherein each photoelectric conversion unit (OEU1, OEU2) includes one or more photoelectric converters (OEC1, OEC2), and each photoelectric converter (OEC1, OEC2) is mounted on an optical waveguide (CWG1, CWG2).

9. The method according to any one of claims 1 to 6, wherein each photoelectric conversion unit (OEU1, OEU2) comprises one or more photoelectric converters (OEC1, OEC2), the Josephson junction (JJ1) and the photoelectric converters (OEC1, OEC2) being implemented on a first substrate, and the optical waveguides (CWG1, CWG2) being implemented on a second, different substrate.

10. 10. The method according to claim 1, wherein Josephson junctions (JJ1) are divided into two or more groups, a first group including first Josephson junctions (JJ1) connected in series, and a second group including second Josephson junctions (JJ1) connected in series, the number of Josephson junctions (JJ1) in the first group being different from the number of Josephson junctions (JJ1) in the second group, and the method includes enabling and disabling the operation of Josephson junctions (JJ1) in the first group in situations where the operation of Josephson junctions (JJ1) in the second group is enabled.

11. The optical signal (CLB1) has a first wavelength (λ １ ) and a second optical pulse sequence (OPAT1) of a different wavelength (λ ２ 11. The method according to claim 1, wherein the first optical pulse sequence (OPAT1) is spectrally separated from the optical signal (CLB1), and the separated first optical pulse sequence (OPAT1) is guided to one or more first photoelectric conversion units (OEU1), and the method comprises guiding the second optical pulse sequence (OPAT2) to one or more second photoelectric conversion units (OEU2).

12. The method according to any one of claims 1 to 11, wherein the photoelectric conversion units (OEU1, OEU2) are integrated directly on the waveguides (CWG1, CWG2).

13. 13. The method according to any one of claims 1 to 12, wherein the optical pulse sequences (OPAT1, OPAT2) are distributed to a plurality of optical transmission lines (CWG1, CWG2) by one or more spectrally selective optical distributors (CDIC1) in a cryogenic chamber (VES1).

14. Voltage pulse (V １ (t), V ２ (t)) to the voltage waveform (V Ｓ１ (t)) and generating a voltage waveform (V Ｆ１ The method of any one of claims 1 to 13, comprising using (t)) as a voltage reference.

15. Voltage waveform (V Ｓ１ (t), V Ｆ１ An apparatus (1000) for generating (t), comprising: - different wavelengths (λ １ , λ ２ an optical pulse generator (OPG1) for providing an optical signal (CLB1) including a plurality of optical pulse sequences (OPAT1, OPAT2); a number of photoelectric conversion units (OEU1, OEU2) that convert a number of optical pulse sequences (OPAT1, OPAT2) into electrical driving current pulses (EPAT1, EPAT2); one or more spectrally selective optical splitters (CSPL1) and a plurality of optical waveguides (CWG1, CWG2) for splitting a plurality of optical pulse sequences (OPAT1, OPAT2) to different photoelectric conversion units (OEU1, OEU2) by wavelength division demultiplexing (WDM); - Electrical driving current pulses (EPAT1, EPAT2) to voltage pulses (V １ (t), V ２ A plurality of Josephson junctions (JJ1) that generate a voltage pulse (V(t)), the Josephson junctions (JJ1) are connected in series, and a voltage pulse (V １ (t), V ２ (t)) to the composite voltage signal (V Ｓ１ a plurality of Josephson junctions (JJ1) forming a gate electrode (t); Equipped with The apparatus (1000) is configured to generate the voltage waveforms (V S1 (t), V F1 (t)) based on the composite voltage signal (V S1 (t)).

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