Active electro-optic quantum converter containing a resonator with switchable nonlinearity

Abstract

A quantum converter device including a microwave resonator component and an optical resonator component, the quantum converter device receiving and converting a set of optical photons and at least one of a voltage pulse or a modulated laser pulse to produce a single microwave photon output.

Description

[Technical Field]

[0001] The present disclosure relates to electro-optical quantum converters, and more particularly to up-converting microwave photons from a superconducting quantum processor to optical photons in the infrared telecommunications band for the dispersal of quantum information. [Background technology]

[0002] Quantum computing generally refers to the use of quantum mechanical phenomena to perform computing and information processing functions. Quantum computing can be contrasted with classical computing, which typically uses transistors to operate on binary values. That is, while classical computers can operate in two basis states, either 0 or 1, quantum computers operate on qubits containing superpositions of both 0 and 1, and can entangle multiple qubits and use interference. Quantum computing is emerging as a new paradigm for solving a wide class of problems that scale poorly on conventional classical high-performance computers. Quantum information technologies based on superconducting qubits have generated much interest in converting quantum states from the microwave to the optical domain. Unlike microwave photons, optical photons can be transmitted by optical fiber, making them suitable for long-distance quantum communication. Furthermore, the optical domain provides access to a large set of well-developed quantum optical tools, such as highly efficient single-photon detectors and long-lived quantum memories. For high-fidelity microwave-to-optical converters, efficient conversion at the single-photon level and low additive noise is required. In particular, networks of quantum computers based on superconducting qubits are likely to require quantum converters that can convert single photons from one frequency to another while maintaining high state-transfer fidelity of quantum information. Summary of the Invention

[0003] The following presents a summary to provide a basic understanding of one or more embodiments of the invention. This summary is not intended to identify key or critical elements or to delineate the scope of particular embodiments or claims. Its sole purpose is to present concepts in a simplified form as a prelude to the more detailed description that is presented later.

[0004] According to one embodiment, a system includes an electro-optical system incorporating a quantum converter device, the quantum converter device executing the following computer-executable components: a microwave resonator and an optical resonator for receiving and converting a set of optical photons and at least one of a voltage pulse or a modulated laser pulse to generate a single microwave photon output.

[0005] In an optional embodiment, the tuning component includes a nonlinear optical material that can be selectively switched on or off with a voltage to alleviate critical coupling requirements.

[0006] According to one embodiment, a system implementation method includes using an electro-optical system incorporating a quantum converter device to execute system executable components to perform the following operations: down-conversion, in which an optical resonator interacts with a microwave resonator to convert a single optical photon into a single microwave photon, where the conversion occurs based on at least one of a voltage pulse applied to the microwave resonator or a modulated laser pulse applied to the optical resonator.

[0007] According to one embodiment, a system implementation method includes using an electro-optical system incorporating a quantum converter device to execute system executable components to perform the following operations: up-conversion, in which an optical resonator interacts with a microwave resonator to convert a single microwave photon into a single optical photon, where the conversion occurs based on at least one of a voltage pulse applied to the microwave resonator or a modulated laser pulse applied to the optical resonator.

[0008] In an optional aspect, the system implementation method further includes mapping, by the system, a tuning component that includes a nonlinear optical material that can be selectively switched on or off with a voltage to alleviate critical coupling requirements. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a block diagram of an exemplary system implementation that upconverts microwave photons from a superconducting quantum processor to optical photons in the infrared telecommunications band for dispersal of quantum information. [Figure 2] 1 is an exemplary flowchart of an efficient electro-optical quantum converter that up-converts microwave photons from a superconducting quantum processor to optical photons in the infrared telecommunications band for the dispersal of quantum information. [Figure 3] FIG. 1 illustrates an exemplary core active electro-optical transducer including a microwave resonator and an optical resonator whose electromagnetic fields overlap each other and overlap a tunable electro-optic material. [Figure 4] 1 is an exemplary cross-sectional view corresponding to a representative type of active electro-optic quantum converter. [Figure 5] 10A-10C are exemplary cross-sectional views of alternative shapes of active electro-optic quantum converters. [Figure 6] 10A-10C are exemplary cross-sectional views of alternative shapes of active electro-optic quantum converters. [Figure 7]FIG. 1 shows an exemplary schematic control structure for an active electro-optical quantum converter operating in an optical to microwave conversion configuration. [Figure 8] FIG. 1 is an exemplary schematic diagram of a quantum converter operating in a microwave-to-optical conversion configuration. [Figure 9] 1 is an exemplary graph of a voltage pulse corresponding to a pulse on the effective nonlinear susceptibility (χ(2)) of an electro-optic material and gating coupling strength (G). [Figure 10] 10 is an exemplary graph of a photon population without a voltage pulse converted from an optical mode to a microwave mode, and Rabi oscillations driven between modes resulting in an oscillation population into two modes. [Figure 11] FIG. 1 is a block diagram of an exemplary, non-limiting operating environment that can facilitate one or more embodiments described herein. [Figure 12] FIG. 1 is a block diagram of an exemplary, non-limiting cloud computing environment in accordance with one or more embodiments of the present disclosure. [Figure 13] FIG. 1 is a block diagram of an exemplary, non-limiting abstraction model layer according to one or more embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0010] The following detailed description is merely illustrative and is not intended to limit the embodiments, or the application and / or uses of the embodiments. Furthermore, there is no intention to be bound by any express or implied information presented in the preceding Summary section or in the Detailed Description section. One or more embodiments will now be described with reference to the drawings, in which like reference numerals are used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a more thorough understanding of one or more embodiments. It will be apparent, however, that in various cases one or more embodiments can be practiced without these specific details.

[0011] This disclosure generally relates to systems and methods for upconverting microwave photons from a superconducting quantum processor (hub) to optical photons in the infrared telecommunications band for the dispersal of quantum information. Such infrared photons can travel long distances in optical fibers ("spokes") without attenuation or interference. At another hub, such as another superconducting quantum processor, another quantum converter can convert the photons from infrared back to the microwave domain. The embodiments disclosed herein use tunable nonlinear optical materials that can be switched on and off with a voltage to avoid the need for critical coupling.

[0012] Quantum computing uses qubits as its essential units instead of classical computing bits. Qubits (e.g., quantum binary digits) are the quantum mechanical analogue of classical bits. While classical bits can only use one of two basis states (e.g., 0 or 1), qubits can use a superposition of their basis states (e.g., α|0〉+β|1〉, where α and β are |α| 2 +|β| 2Quantum computers (i.e., computers that use qubits instead of classical bits only) can theoretically store exponentially more information than the same number of classical bits. Thus, quantum computers (e.g., computers that use qubits instead of classical bits only) could theoretically quickly solve problems that would be extremely difficult for classical computers. A classical computer's bits are simple binary digits with a value of either 0 or 1. Switches, valves, magnets, coins, and almost any other device with two distinct states can serve to represent a classical bit. A qubit, imbued with quantum mystique, can occupy a superposition of 0 and 1 states. It's not that a qubit can have an intermediate value, such as 0.63; when a qubit's state is measured, the result is either 0 or 1. However, during the course of a computation, the qubit can behave as if it were in a superposition of, say, 63 percent 0 and 37 percent 1 states. A typical quantum program requires coordination between the quantum and classical parts of the computation. One way to think about a general quantum program is to identify the processes and abstractions involved in specifying a quantum algorithm, converting the algorithm into an executable form, conducting experiments or simulations, and analyzing the results. A concept that runs throughout these processes is the use of intermediate representations. An intermediate representation (IR) of a computation is neither its source language description nor the target machine instructions, but something in between. A compiler can use several IRs during the process of translating and optimizing a program. The input is source code describing the quantum algorithm and compile-time parameters. The output is a combined quantum / classical program expressed using high-level IR. Quantum computers differ from classical computers in that they are probabilistic, meaning that measuring the algorithm's output provides a reasonable solution within a confidence interval specific to the algorithm. The computation is then repeated until a satisfactory degree of plausibility of the solution can be achieved.

[0013] By processing information using the laws of quantum mechanics, quantum computers offer novel ways to perform computational tasks such as molecular computing, optical photons, optimization, and many more. Numerous algorithms have been introduced to efficiently perform such computational tasks. Furthermore, many promising solid-state implementations of qubits have been demonstrated, including superconducting qubits of various flavors, spin qubits, and charge qubits in various material systems. Typical characteristic energy scales for these systems correspond to radiation frequencies on the order of 5–10 GHz, allowing them to be easily manipulated using commercial microwave technology. Proposals for novel quantum information processing technologies often rely on quantum networks, linking large numbers of qubits or groups of qubits together to enable quantum-secure communication, novel metrology techniques, or distributed quantum computing. However, microwave-frequency photons are difficult to transmit over long distances. Typical attenuation in low-loss microwave cables at 10 GHz exceeds 1 dBm-1, which is significantly inferior to optical fiber, which has a loss of less than 0.2 dBm-1 at telecommunication wavelengths (λ ≈ 1550 nm, f ≈ 193 THz). Furthermore, at temperatures above 1 K, a substantial thermally generated background of microwave photons exists, which prevents the transmission of microwave signals with single-photon fidelity. The advantages of transmitting quantum information over fiber are immediately apparent. Networks of quantum computers will likely require quantum converters that can convert single photons from one frequency to another while maintaining high state-transfer fidelity of the quantum information. In particular, the hub-and-spoke distributed quantum computing paradigm, in which superconducting qubit quantum computers are networked over long distances, requires quantum conversion, since microwave photons, which store quantum information in superconducting qubits, are not compatible with room-temperature operation. As mentioned above, the energy of microwave photons is less than the thermal background energy at room temperature, making room-temperature quantum information links at microwave frequencies either impossible or extremely challenging.Thus, the embodiments described and claimed herein provide a unique methodology for upconverting microwave photons from a superconducting quantum processor to optical photons in the infrared telecommunications band for quantum information dispersal. Such infrared photons can travel long distances in optical fiber without attenuation or interference. In another superconducting quantum processor, another quantum converter can convert the photons from infrared back to the microwave domain.

[0014] FIG. 1 illustrates a block diagram of an exemplary system 100 that can access and process data using the variable computing components shown, in accordance with one or more embodiments described herein. System 100 can use machine learning to evaluate and identify large amounts of data in various formats and facilitate the process of training neural networks or other types of models. System 100 can also generate predictive recommendations for individual levels, including context, in accordance with one or more embodiments described herein. Aspects of the systems (e.g., system 100), devices, or processes described in this disclosure can constitute machine-executable components embodied within a machine, e.g., embodied in one or more computer-readable media associated with one or more machines. Such components, when executed by one or more machines (e.g., computers, computing devices, virtual machines, etc.), can cause the machine to perform the operations described herein. Repeated descriptions of similar elements used in one or more embodiments described herein have been omitted for the sake of brevity.

[0015] System 100 facilitates that microwave photons from a superconducting quantum processor can be upconverted to optical photons in the infrared telecommunications band for quantum information dispersal. Such infrared photons can travel long distances in optical fiber with nominal attenuation or interference. At another hub, such as another superconducting quantum processor, another quantum converter can convert the photons from infrared back to the microwave domain.

[0016] System 100 may optionally include a server device, one or more networks, and one or more devices (not shown). System 100 may also include an electro-optical system 102 coupled to or otherwise associated with a quantum converter device 110. Quantum converter device 110 may include and be operatively coupled to various components, including, but not limited to, a microwave resonator 104, an optical resonator 106, and a tuning component 108. In a down-conversion method, an optical resonator interacts with a microwave resonator to convert a single optical photon into a single microwave photon, where the conversion occurs based on at least one of a voltage pulse applied to the microwave resonator or a modulated laser pulse applied to the optical resonator using tuning component 108, thereby generating a single microwave photon output 112.

[0017] The quantum converter device 110 may include and be operatively coupled to various components, including, but not limited to, a microwave resonator 104, an optical resonator 106, and a tuning component 108. In an up-conversion method, the optical resonator interacts with the microwave resonator to convert a single microwave photon into a single optical photon, where the conversion occurs based on at least one of a voltage pulse applied to the microwave resonator or a modulated laser pulse applied to the optical resonator using the tuning component 108, thereby generating a single optical photon output 112.

[0018] System 100 may be any suitable computing device or set of computing devices that can be communicatively coupled to a device, non-limiting examples of which may include, but are not limited to, a server computer, a computer, a mobile computer, a mainframe computer, an automated testing system, a network storage device, a communications device, a web server device, a network switching device, a network routing device, a gateway device, a network hub device, a network bridge device, a control system, or any other suitable computing device. The device may be any device capable of communicating information with system 100 and / or any other suitable device capable of using information provided by system 100. It will be appreciated that system 100, a component, a model, or a device may be equipped with communications components (not shown) that enable communication between systems, components, models, devices, etc. across one or more networks.

[0019] The various components of system 100 may be connected directly or through one or more networks. Such networks may include wired and wireless networks, including, but not limited to, a cellular network, a wide area network (WAN) (e.g., the Internet), or a local area network (LAN), non-limiting examples of which include cellular, WAN, Wireless Fidelity (Wi-Fi), Wi-Max, WLAN, radio communication, microwave communication, satellite communication, optical communication, acoustic communication, or any other suitable communication technology. Moreover, the systems and / or devices described above are described with respect to interactions between several components. It may be recognized that such systems and components can include those components or subcomponents specified therein, some of the specified components or subcomponents, or additional components, or combinations thereof. Subcomponents may also be implemented as components communicatively coupled to other components rather than being contained within a parent component. Furthermore, one or more components and / or subcomponents may be combined into a single component providing aggregate functionality. A component may also interact with one or more other components not specifically described herein for the sake of brevity, but known by those skilled in the art.

[0020] The subject computer processing systems, methods, apparatus, or computer program products, or combinations thereof, may be used to solve new problems that arise through developments in technology, computer networks, the Internet, and the like.

[0021] Networks of quantum computers will likely require quantum converters capable of converting single photons from one frequency to another while maintaining high fidelity in the state transfer of quantum information. In particular, because microwave photons, which store quantum information in superconducting qubits, are incompatible with room-temperature operation, a hub-and-spoke distributed quantum computing paradigm in which superconducting qubit quantum computers are networked over long distances requires quantum conversion. Because the energy of microwave photons is smaller than the thermal background energy at room temperature, room-temperature quantum information links at microwave frequencies are either impossible or extremely challenging. Therefore, preserving quantum information in the microwave domain over long distances or high temperatures is challenging. Because of its low energy, microwave domains are constantly being generated. Preserving the quantum nature of information when transferring information from one quantum computer to another is useful. To achieve this property, the photon frequency must be converted or translated from the microwave domain to the infrared telecommunications domain. Infrared photons can be sent over long distances using ordinary optical fiber while preserving their quantum state. Thus, embodiments disclosed herein provide a promising solution to this problem by upconverting microwave photons from a superconducting quantum processor (the "hub") to optical photons in the infrared telecommunications band for dispersal of quantum information. Such infrared photons can travel long distances in optical fibers (the "spokes") without attenuation or interference. As mentioned, at another hub, such as another superconducting quantum processor, another quantum converter can convert the photons from infrared back to the microwave domain.

[0022] FIG. 2 illustrates an exemplary flowchart of a methodology associated with an electro-optical quantum converter that upconverts microwave photons from a superconducting quantum processor to optical photons in the infrared telecommunications band for quantum information dispersal. As indicated by block 202, a superconducting microwave resonator is operable to receive a single microwave photon. An optical resonator component has a magnetic field that overlaps with the superconducting microwave resonator. As indicated by block 204, the optical resonator component converts a set of optical photons and at least one of a voltage pulse or a modulated laser pulse to generate a single microwave photon output. A modulated optical signal source is operable to upconvert the single microwave photon to a single optical photon for communication over an optical communication medium. As indicated by block 206, the tuning component includes a nonlinear optical material that can be selectively switched on or off with a voltage to alleviate critical coupling requirements.

[0023] Effective χ 2 The nonlinear susceptibility is selectively switched on by a voltage and selectively switched off when the conversion is complete. The nonlinear optical material exhibits a strong third-order nonlinear susceptibility (χ (3) ) and a non-zero χ in equilibrium (2) The optical resonator pumped by the laser is gated with a modulator, and the microwave resonator component is coupled to a pulsed voltage source through a switch and an inductor. An LC band-pass filter can be tuned to the bandwidth of the voltage pulse.

[0024] Quantum converters can transfer quantum information between different systems. There are few general challenges for quantum converters. While nonlinear optics, typically used to convert optical frequencies, often relies on high optical photon fluxes, quantum converters can operate with single photons. Second, preserving quantum information requires minimal microwave and optical losses. However, many nonlinear optical materials are lossy in the microwave domain. Microwave-to-optical photon conversion would be useful for future quantum networks interconnecting remote superconducting quantum computers with optical fiber. Furthermore, the very large frequency difference between microwave and infrared photons presents an additional challenge to nonlinear optical approaches for photon frequency conversion. In addition to demonstrating high fidelity in quantum state transfer, quantum converters must also have sufficient bandwidth to be compatible with system-level performance. True microwave-to-optical or optical-to-microwave quantum converters have not yet been demonstrated. However, many prototype devices incorporating advances toward quantum converters have been fabricated. In general, these devices can be divided into those based on resonators that mediate the coupling between microwave and optical photons, and those based on pure nonlinear optics with no mediating degree of freedom. Examples of mediating degrees of freedom include mechanical resonators, atomic optical or spin transitions, electronic states of defect centers in crystals, or magnum states.

[0025] There are several different approaches to address the problem of quantum networking using single photons. Intermediaries such as mechanical oscillators can be used to convert the frequency of photons. These embodiments focus on direct frequency conversion of nominal optics based on nonlinear optical properties. In the case of single photons, microwave resonators are coupled to optical resonators incorporating nonlinear optical media. These resonators need to be of high quality to compensate for the fact that single photons are used. Among the quantum converters based on nonlinear optics, the simplest is the one based on nonzero χ (2) Three-wave mixing in a material with nonlinear susceptibility. In this scheme, a microwave resonator and an optical resonator are designed to have overlapping electromagnetic fields and resonant modes whose angular frequency ω satisfies the following condition: ω a -ω b =ω c , where a and b are optical cavity modes and c is a microwave cavity mode. This condition allows for Raman-type sum or difference frequency generation via three-wave mixing.

[0026] 3 illustrates an exemplary core active electro-optic converter consisting of a microwave resonator and an optical resonator whose electromagnetic fields overlap each other and overlap with a tunable electro-optic material. In the electro-optic quantum conversion scheme represented by block 300, the mode (angular frequency ω) of an optical resonator 302 on an optical waveguide 304 is tuned. a Mode a) with angular frequency ω c Mode c) with angular frequency ω a ~ω c , an input microwave photon 310 has its frequency converted to an optical photon in mode b of resonator 302. This differential mode generation is a type of Raman process. Alternatively, instead of a microwave photon 310 applied to resonator c as indicated by block 306, a single optical photon 328 can be converted to an optical photon of angular frequency ω a ~ωb may be applied to the optical resonator 302 at resonance ω c 302. Alternatively, the signal microwave mode and the excitation microwave mode (modes a and b) may be swapped, and the frequency conversion operates via sum frequency generation instead of difference frequency generation. The core of the active electro-optic converter consists of a microwave resonator 306 and an optical resonator 302, whose electromagnetic fields overlap each other and the tunable electro-optic material. A typical way to make an electro-optic material tunable is to have the electro-optic material have a second-order nonlinear optical susceptibility χ of 0. (2) and a non-zero third-order susceptibility (χ (3) ), in which case the voltage pulse has an effective χ (2)Nonlinearity can be induced. The microwave and optical resonators are coupled to microwave and optical transmission lines 314 and 304, respectively. The optical resonator is excited with an external laser 308, which is gated by a modulator 316. The microwave resonator 306 is connected to pulsed voltage sources 318 and 320 through a switch 322 and an inductor 324. The inductor 324 (of inductance L), together with the capacitance formed between the microwave resonator waveguide 326 and the ground plane, forms an LC band-pass filter. L may be selected to tune this filter to the bandwidth of the voltage pulse 320. Either the pulsed voltage 320 applied to the material or the pulsed or modulated laser 308 is applied to the optical waveguide 304 to drive Rabi oscillations between the microwave photon population 330 and the optical photon population 332. Thus, in this schematic layout of the device, an optical resonator 302 is coupled to an optical waveguide 304 that can send excitation single photons and couple them to a microwave resonator 306, which is coupled to the transmission line. These embodiments therefore add voltage and optical modulators to allow the normality to be switched. The rate must be balanced so that microwave photons can be converted to optical photons and exit the device. If the coupling rate is too small, the photons will not convert, and if it is too large, an oscillatory response will occur.

[0027] The theory underlying this electro-optic quantum conversion method was developed by Tsang ["Cavity quantum electro-optics. II. Input-output relations between traveling optical and microwave fields," Phys. Rev. A, 84, 1 (2011)]. In this work, the efficiency of the conversion process was calculated based on various rates defining the resonator. These rates include the rate of the excited photon population, the external and internal decay rates of the microwave and optical resonators, and the coupling rate between the two resonators. The efficiency of quantum conversion is defined as the fraction of microwave photons successfully converted to optical photons (or vice versa). It has been determined that the efficiency of quantum conversion is maximized at the critical coupling condition, where the coupling rate between the optical and microwave resonators is precisely balanced by their decay rates, allowing energy to flow in only one direction between the input and output photons. If the coupling rate is higher than the rate prescribed by the critical coupling condition, energy can oscillate between the microwave and optical resonators. If the coupling rate is too low, the input photons may undergo excessive decay before being converted to the output frequency. This critical coupling condition can impose a difficult trade-off between the efficiency and bandwidth of the quantum conversion process. It would be desirable to maximize the conversion rate by making the coupling rate between the resonators as high as possible. Therefore, an electro-optic quantum converter that does not rely on critical coupling would be novel and advantageous.

[0028] Figure 4 illustrates an exemplary cross-section corresponding to a representative type of active electro-optic quantum converter. This block diagram 400 is a cross-section of a representative type of active electro-optic quantum converter corresponding to the bold dotted line in Figure 3 described above. An embedded high refractive index material is surrounded by a lower refractive index material, which acts as an optical waveguide, and a superconducting transmission line is fabricated on the top surface of the substrate. A representative example of this type of system is a Si(4) surrounded by Si(4). 1-x Ge xThe resulting optical waveguide 406 is a superconducting microwave resonator and transmission line 404, which is fabricated on top of this optical waveguide from a material such as Nb, Al, or TiN, represented by the ground plane 402. The electromagnetic fields in the microwave range and the optical resonator have significant χ (2) or χ (3) The nonlinear susceptibility can be either ∑ ... (2) The nonlinear susceptibility is simply switched on by a voltage as needed, and then switched off once the conversion process is complete. The voltage can be thought of as driving Rabi oscillations, with the microwave-to-optical and optical-to-microwave populations alternating as π pulses. This type of conversion scheme is similar to the χ that exists in equilibrium. (2) or the steady-state effective χ (2) This is called the "active" electro-optical scheme to distinguish it from materials with a strong third-order nonlinear susceptibility (χ (3) ) The centrosymmetric material may be a material with a χ (2) = 0 (due to symmetry). However, if we define the electric field as χ (3) When applied to materials, the effective χ (2) Typical examples of such materials are Si or Si 1-x Ge 1-x Alternatively, a non-zero χ (2) A material with χ modulated by an applied voltage will also (2) An alternative way to actively drive a π pulse between the microwave and optical resonators (e.g., swapping the photon populations in the two resonators) is to use the χ (2) or effective χ (2)The solution is to modulate the pump laser on and off for the duration of the π pulse, while leaving π unmodulated. This can be achieved using an optical modulator, which can be either a conventional discrete optical modulator or an optical modulator integrated on a chip with an active quantum converter.

[0029] FIG. 5 illustrates an exemplary cross-section of another geometry of an active electro-optic quantum converter. This block diagram 500 is a cross-section of another geometry corresponding to the dotted bold line in FIG. 3 of a representative type of active electro-optic quantum converter. A superconducting microwave resonator and transmission line 506 would be fabricated on top of this optical waveguide from a material such as Nb, Al, or TiN, as indicated by block 502. Here, the high-index photonic waveguide 504 is fabricated on top of another film or substrate instead of being embedded in another material. Representative examples of that substrate would be LiNbO3, AlN, SiC, or BaTiO3, as indicated by block 508.

[0030] FIG. 6 illustrates an exemplary cross-sectional view of another shape of an active electro-optic quantum converter. This block diagram 600 is a cross-sectional view of another shape corresponding to the dotted bold line in FIG. 3 of a representative type of active electro-optic quantum converter. A superconducting microwave resonator and a transmission line, represented by block 608, would be fabricated on top of this optical waveguide from a material such as Nb, Al, or TiN, represented by block 602. Here, neither the photonic waveguide, represented by block 604, nor the substrate, represented by block 610, need be electro-optical. Rather, an electro-optic material, such as an electro-optic polymer, is disposed on top of the microwave resonator and optical resonator. General benefits of active electro-optic quantum converters over passive electro-optic quantum converters include higher bandwidth, since the coupling rate can exceed the rate specified by the critical coupling condition. Conversion can be actively turned on and off as needed for quantum networking. The length of the voltage or optical pulse can be fine-tuned as needed to optimize the microwave-to-optical or optical-to-microwave π pulse. In addition to Rabi drive, more advanced quantum control protocols such as bang-bang control or Laundau-Zener control can be used to further increase the conversion rate and / or efficiency.

[0031] To simulate the dynamics of the active electro-optical transducer, the following Hamiltonian function H is developed:

[0032]

number

[0033]

number

[0034]

number

[0035] Figure 7 illustrates an exemplary schematic control structure for an active electro-optic quantum converter operating in an optical-to-microwave conversion configuration. The core of the structure, shown in block 700, is a coupled microwave and optical resonator structure 710. The inputs are a pump laser 704, a voltage source pulse generator 702, and a single-photon optical source 706. Either the voltage source or the pump laser, or both, may be modulated by an optical modulator 708 or pulsed to actively drive the quantum conversion operation. The output is a single-photon microwave source 712, which carries the converted quantum information of the input optical source.

[0036] FIG. 8 illustrates an exemplary schematic of a quantum converter operating in a microwave-to-optical conversion configuration. The core of the structure, shown in block 800, is a coupled microwave and optical resonator structure 810. This is the same schematic as FIG. 7 described above, except the quantum converter is operating in a microwave-to-optical conversion configuration. Either or both of the voltage source 802 or pump laser 804 may be modulated by an optical modulator 808 or pulsed to actively pulse the quantum conversion operation. The inputs here are a single-photon microwave source 806, a pump laser 804, and a voltage source 802. The output is a single-photon optical source, shown by block 812. To solve the equations of motion, the resonator coupling parameter G is chosen as a constant (e.g., as in a passive electro-optical quantum converter) or is varied via a step function, where G is turned on at t=0 and then at t=τ pulse and G=0. The following parameters are ω c =2π(5GHz) , which is, for example, a typical frequency δ of a superconducting qubit that sets the optical frequency difference to a microwave resonance. b =2p(5GHz). K b =K b,ex =ω b / Q b , where Q b is the quality factor of the optical resonator Q b =6×10 7 K c =K c,ex =ω c / Q c , where Q c is the quality factor of the microwave resonator Q c =100 b in =0,c in = 1 (e.g., the population starts in microwave mode)

[0037] Figure 9 shows the effective nonlinear susceptibility (χ (2) 9 illustrates an exemplary graph of the gating of the voltage pulse and coupling strength (G) corresponding to a pulse at t. G is pulsed at 0 ns and 7 ns as shown in graph 900, with G=200 MHz, C=100, and t pulse = 7ns to show the solution to the equation mentioned in the paragraph above. A voltage pulse intensity lasting 7ns drives a single Rabi oscillation of a single photon ensemble from the microwave mode ensemble to the optical mode ensemble with an efficiency rate of 60%. The voltage pulse drives the effective χ of the electro-optic material. (2) 902 corresponds to a pulse at 100 kJ / s, and therefore corresponds to gating of the coupling strength (G). Alternatively, the excitation laser may be gated on and off. In this graph, pulse strength is determined by time (ns) on the x-axis, indicated by block 902, and power (%) on the y-axis, indicated by block 904.

[0038] FIG. 10 illustrates an example graph showing a photon population converted from optical mode to microwave mode without a voltage pulse, and Rabi oscillations driven between modes, resulting in an oscillation population for the two modes. In both of these cases, shown in graphs 1000 and 1002, no voltage pulse is present. In graph 1000, G=20 MHz and C=1, where a critical condition is reached. In this critical coupling case, the photon population is converted from optical mode to microwave mode, but the process is only 10% efficient using 40 ns. Approximately 10% microwave-to-optical conversion efficiency is achieved in 40 ns. In graph 1002, G=200 MHz and C=100, where the power being converted to the optical mode is initially high but decays to near zero over time due to the decay of the Rabi oscillations. In this case, the Rabi oscillations are driven between modes, resulting in an oscillation population for the two modes. Passive devices result in lower efficiency, and strong pulses can result in an oscillatory response that eventually collapses and produces no output. The pulsed configuration shown in FIG. 9 has a conversion efficiency of 60%, which is six times higher than the efficiency of the graph shown in FIG. 10, and the conversion rate of graph 1002 is over five times higher than that of FIG. 9. These results indicate that switching G on and off can enable faster and more efficient electro-optical quantum conversion by using critical coupling. The combined results of varying the parameter G and pulsing G are shown in the table below, as depicted in the graphs referenced above.

[0039] [Table 1] These embodiments therefore propose a solution in which microwave photons from a superconducting quantum processor are converted into optical photons in the infrared telecommunications band for the dispersal of quantum information. In this way, the infrared photons can travel long distances in optical fibers without interference. And, at another hub or superconducting quantum processor, another quantum converter can convert the photons from infrared back into the microwave domain.

[0040] To provide context for various aspects of the disclosed subject matter, Figure 11 and the following discussion are intended to provide a general description of a suitable environment in which various aspects of the disclosed subject matter may be implemented. Figure 11 illustrates a block diagram of an exemplary, non-limiting operating environment that may facilitate one or more embodiments described herein. Repeated descriptions of similar elements used in other embodiments described herein have been omitted for the sake of brevity.

[0041] 11, a suitable operating environment 1100 for implementing various aspects of the present disclosure may also include a computer 1112. The computer 1112 may also include a processing unit 1114, a system memory 1116, and a system bus 1118. The system bus 1118 couples system components, including but not limited to the system memory 1116, to the processing unit 1114. The processing unit 1114 may be any of a variety of available processors. Dual microprocessors and other multi-processor architectures may also be employed as the processing unit 1114. The system bus 1118 may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus or external bus, and / or a local bus using any of a variety of available bus architectures, including, but not limited to, Industry Standard Architecture (ISA), Micro Channel Architecture (MSA), Enhanced ISA (EISA), Intelligent Drive Electronics (IDE), VESA Local Bus (VLB), Peripheral Component Interconnect (PCI), Card Bus, Universal Serial Bus (USB), Advanced Graphics Port (AGP), Firewire® (IEEE 1394), and Small Computer System Interface (SCSI).

[0042] The system memory 1116 may also include volatile memory 1120 and nonvolatile memory 1122. A basic input / output system (BIOS), containing the basic routines for transferring information between elements within the computer 1112, such as during start-up, is stored in the nonvolatile memory 1122. The computer 1112 may also include removable / non-removable, volatile / non-volatile computer storage media. FIG. 11 illustrates, for example, disk storage 1124. The disk storage 1124 may also include devices such as, but not limited to, a magnetic disk drive, a floppy disk drive, a tape drive, a Jaz drive, a Zip drive, an LS-100 drive, a flash memory card, or a memory stick. The disk storage 1124 may also include storage media separate from or combined with other storage media. A removable or non-removable interface, such as interface 1126, is typically used to facilitate connection of disk storage 1124 to system bus 1118. Figure 11 also illustrates software that acts as an intermediary between users and the basic computer resources described in preferred operating environment 1100. Such software may also include, for example, operating system 1128. Operating system 1128, which may be stored on disk storage 1124, acts to control and allocate resources of computer 1112.

[0043] System applications 1130 take advantage of the management of resources by operating system 1128 through program modules 1132 and program data 1134 stored, for example, either in system memory 1116 or on disk storage 1124. It should be appreciated that the present disclosure may be implemented with various operating systems or combinations of operating systems. Users enter commands or information into computer 1112 through input devices 1136. Input devices 1136 include, but are not limited to, pointing devices such as a mouse, trackball, stylus, or touch pad, keyboard, microphone, joystick, game pad, satellite dish, scanner, TV tuner card, digital camera, digital video camera, web camera, etc. These and other input devices connect to processing unit 1114 through system bus 1118 via interface ports 1138. Interface ports 1138 include, for example, serial ports, parallel ports, game ports, and universal serial buses (USBs). Output devices 1140 use some of the same types of ports as input devices 1136. Thus, for example, a USB port can be used to provide input to computer 1112 and output information from computer 1112 to output devices 1140. Output adapters 1142 are provided to illustrate that there are some output devices 1140, such as monitors, speakers, and printers, among other output devices 1140, that require special adapters. Output adapters 1142 include, by way of example only and not limitation, video and sound cards that provide a means of connection between output devices 1140 and system bus 1118. It should be noted that other devices and / or systems of devices, such as remote computer 1144, provide both input and output capabilities.

[0044] The computer 1112 can operate in a networked environment using logical connections to one or more remote computers, such as a remote computer 1144. The remote computer 1144 may be a computer, server, router, network PC, workstation, microprocessor-based appliance, peer device, or other common network node, and typically includes many or all of the elements described relative to the computer 1112. For simplicity, only a memory storage device 1146 is illustrated with the remote computer 1144. The remote computer 1144 is logically connected to the computer 1112 through a network interface 1148 and then physically connected via a communication connection 1150. The network interface 1148 encompasses wired and / or wireless communication networks such as a local area network (LAN), a wide area network (WAN), a cellular network, and the like. LAN technologies include Fiber Distributed Data Interface (FDDI), Copper Distributed Data Interface (CDDI), Ethernet, Token Ring, and the like. WAN technologies include, but are not limited to, point-to-point links, circuit-switched networks such as Integrated Services Digital Networks (ISDN) and variations thereon, packet-switched networks, and Digital Subscriber Lines (DSL). Communications connection 1150 refers to the hardware / software employed to connect network interface 1148 to system bus 1118. For clarity of illustration, communications connection 1150 is shown internal to computer 1112, but it may also be external to computer 1112. The hardware / software for connecting to network interface 1148 may also include internal and external technologies such as modems, including, by way of example only, ordinary telephone-grade modems, cable modems, and DSL modems, ISDN adapters, and Ethernet cards.

[0045] Referring now to FIG. 12 , an exemplary cloud computing environment 1250 is illustrated. As shown, the cloud computing environment 1250 includes one or more cloud computing nodes 1210 with which local computing devices used by cloud consumers can communicate, such as, for example, a personal digital assistant (PDA) or cellular phone 1254A, a desktop computer 1254B, a laptop computer 1254C, or an automotive computer system 1254N, or combinations thereof. Although not illustrated in FIG. 12 , the cloud computing nodes 1210 may further include a quantum platform (e.g., quantum computer, quantum hardware, quantum software, etc.) with which local computing devices used by cloud consumers can communicate. The nodes 1210 can communicate with each other. The nodes 1210 may be physically or virtually grouped (not shown) in one or more networks, such as a private cloud, community cloud, public cloud, or hybrid cloud, or combinations thereof, as described herein above. This enables the cloud computing environment 1250 to provide infrastructure, platform, and / or software as a service without requiring cloud consumers to maintain resources on their local computing devices. It should be understood that the types of computing devices 1254A-N shown in Figure 12 are intended to be illustrative only, and that the computing nodes 1210 and the cloud computing environment 1250 can communicate with any type of computerized device over any type of network and / or network-addressable connection (e.g., using a web browser).

[0046] Referring now to Figure 13, a set of functional abstraction layers provided by cloud computing environment 1250 (Figure 12) is shown. It should be understood that the components, layers, and functions shown in Figure 13 are intended to be illustrative only, and embodiments of the present invention are not limited thereto. As shown, the following layers and corresponding functions are provided:

[0047] Hardware and software layer 1360 includes hardware and software components. Examples of hardware components include mainframe 1361, RISC (reduced instruction set computer) architecture-based server 1362, server 1363, blade server 1364, storage device 1365, and network and networking components 1366. In some embodiments, software components include network application server software 1367, quantum platform routing software 1368, or quantum software (not illustrated in FIG. 13 ), or a combination thereof.

[0048] Virtualization layer 1370 provides an abstraction layer from which the following example virtual entities may be provided: virtual servers 1371, virtual storage 1372, virtual networks including virtual private networks 1373, virtual applications and operating systems 1374, and virtual clients 1375.

[0049] In one example, management layer 1380 can provide the functions described below. Resource provisioning 1381 provides dynamic procurement of computing and other resources utilized to perform tasks within the cloud computing environment. Metering and pricing 1382 provides cost tracking as resources are utilized within the cloud computing environment and bills or invoices for the consumption of these resources. In one example, these resources can include application software licenses. Security provides identity verification of cloud consumers and tasks, as well as protection for data and other resources. User portal 1383 provides access to the cloud computing environment to consumers and system administrators. Service level management 1384 provides allocation and management of cloud computing resources so that requested service levels are met. Service level agreement (SLA) planning and fulfillment 1385 provides advance arrangement and procurement of cloud computing resources in anticipation of future requirements according to SLAs.

[0050] The workload layer 1390 provides examples of functionality for which a cloud computing environment may be utilized. Non-limiting examples of workloads and functions that may be provided from this layer include mapping and navigation 1391, software development and lifecycle management 1392, virtual classroom instructional delivery 1393, data analytics processing 1394, transaction processing 1395, and quantum state preparation software 1396.

[0051] The present invention may be a system, method, apparatus, or computer program product, or any combination thereof, at any possible level of integration of technical detail. The computer program product may include a computer-readable storage medium having computer-readable program instructions thereon for causing a processor to perform aspects of the present invention. The computer-readable storage medium may be a tangible device capable of retaining and storing instructions for use by an instruction-execution device. The computer-readable storage medium may be, for example, but not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the above. A non-exhaustive list of more specific examples of computer-readable storage media could also include portable computer diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disk read-only memory (CD-ROM), digital versatile disk (DVD), memory stick®, floppy® disk, mechanically encoded devices such as punch cards or groove ridge structures with instructions recorded thereon, and any suitable combination of the above. As used herein, computer-readable storage media should not be construed as being ephemeral signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses passing through fiber optic cable), or electrical signals transmitted through wires.

[0052] The computer-readable program instructions described herein may be downloaded from a computer-readable storage medium to a respective computing / processing device or to an external computer or external storage device over a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network may include copper transmission cables, optical transmission fiber, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in the computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in a computer-readable storage medium within the respective computing / processing device. The computer readable program instructions for carrying out the operations of the present invention may be source code or object code written in any combination of one or more programming languages, including assembler instructions, Instruction Set Architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, configuration data for integrated circuits, or object-oriented programming languages ​​such as Smalltalk®, C++, etc., and procedural programming languages ​​such as the "C" programming language or similar programming languages. The computer readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server.In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (e.g., through the Internet using an Internet service provider). In some embodiments, electronic circuitry, including, for example, a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), can execute computer-readable program instructions by utilizing state information of the computer-readable program instructions to personalize the electronic circuitry to implement aspects of the present invention.

[0053] Aspects of the present invention are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions. These computer-readable program instructions may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, when executed by a processor of the computer or other programmable data processing apparatus, create means for implementing the functions / acts specified in one or more blocks of the flowchart illustrations and / or block diagrams. These computer-readable program instructions may also be stored on a computer-readable storage medium, such that the computer-readable storage medium having the instructions stored therein comprises an article of manufacture containing instructions that implement aspects of the functions / acts specified in one or more blocks of the flowchart illustrations and / or block diagrams, and can direct a computer, programmable data processing apparatus, or other device, or combination thereof, to function in a particular manner. The computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational operations to be performed on the computer, other programmable apparatus, or other device to produce a computer-implemented process, such that the instructions, when executed on the computer, other programmable apparatus, or other device, implement the functions / operations specified in one or more blocks of the flowcharts and / or block diagrams.

[0054] The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in the flowcharts or block diagrams may represent a module, segment, or portion of instructions, which includes one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the blocks may occur out of the order noted in the figures. For example, two blocks shown in succession may in fact be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending on the functionality involved. It should also be noted that each block in the block diagrams and / or flowchart diagrams, and combinations of blocks in the block diagrams and / or flowchart diagrams, may be implemented by a special-purpose hardware-based system that performs the specified functions or operations or executes a combination of special-purpose hardware and computer instructions.

[0055] Although the present subject matter has been described above in the general context of computer-executable instructions for a computer program product running on a computer and / or multiple computers, those skilled in the art will recognize that the present disclosure can also be implemented in combination with other program modules. Generally, program modules include routines, programs, components, data structures, etc. that perform particular tasks and / or implement particular abstract data types. Moreover, those skilled in the art will recognize that the computer-implemented methods of the present invention can be practiced with other computer system configurations, including single-processor or multi-processor computer systems, minicomputing devices, mainframe computers, and other computer systems, including computers, handheld computing devices (e.g., PDAs, phones), microprocessor-based or programmable consumer or industrial electronics, etc. The illustrated aspects may also be practiced in distributed computing environments where tasks are performed by remote processing devices linked through a communications network. However, some, if not all, aspects of the present disclosure can be practiced on stand-alone computers. In a distributed computing environment, program modules may be located in both local and remote memory storage devices.

[0056] As used herein, terms such as “component,” “system,” “platform,” and “interface” can refer to and / or include a computer-related or computing machine-related entity having one or more specific functionalities. The entities disclosed herein may be hardware, a combination of hardware and software, software, or software in execution. For example, a component may be, but is not limited to, a process running on a processor, a processor, an object, an executable, a thread of execution, a program, or a computer, or combinations thereof. By way of illustration, both an application running on a server and the server may be a component. One or more components may reside within a process and / or thread of execution, and a component may be localized on one computer or distributed between two or more computers, or both. In another example, each component may execute from various computer-readable media having various data structures stored thereon. Components may communicate through local and / or remote processes, such as according to signals having one or more data packets (e.g., data from one component interacting with another component in a local system, a distributed system, and / or other systems via signals across a network such as the Internet). As another example, a component may be a device with specific functionality provided by mechanical parts operated by electrical or electronic circuitry that is operated by a software or firmware application executed by a processor. In such cases, the processor may be internal or external to the device and may execute at least a portion of the software or firmware application.As yet another example, a component may be a device that provides specific functionality without mechanical parts through electronic components, where the electronic components may include a processor or other means for executing software or firmware that at least partially confers the functionality of the electronic component. In one aspect, a component may emulate the electronic component via, for example, a virtual machine in a cloud computing system.

[0057] Additionally, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or." That is, unless otherwise specified or clear from the context, "X uses A or B" is intended to mean any of the natural inclusive permutations. That is, if X uses A, X uses B, or X uses both A and B, then "X uses A or B" is satisfied under any of the above examples. Moreover, as used in this specification and the accompanying drawings, the articles "a" and "an" should generally be construed to mean "one or more" unless otherwise specified or clear from the context that the singular form is intended. As used herein, the term "example" and / or "exemplary" is utilized to mean serving as an example, instance, or illustration. For the avoidance of doubt, the subject matter disclosed herein is not limited by such examples. Additionally, any aspect or design described herein as "example" and / or "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects or designs, nor is it meant to exclude equivalent exemplary structures and techniques known to those skilled in the art.

[0058] As used herein, the term "processor" may refer to substantially any computing processing unit or device, including, but not limited to, a single-core processor, a single processor with software multithreading execution capabilities, a multi-core processor, a multi-core processor with software multithreading execution capabilities, a multi-core processor with hardware multithreading technology, a parallel platform, and a parallel platform with distributed shared memory. Furthermore, a processor may refer to an integrated circuit, an application-specific integrated circuit (ASIC), a digital signal processor (DSP), a field-programmable gate array (FPGA), a programmable logic controller (PLC), a complex programmable logic device (CPLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof, designed to perform the functions described herein. Furthermore, a processor may utilize nanoscale architectures, such as, but not limited to, molecular and quantum dot-based transistors, switches, and gates, to optimize space usage or enhance performance of user equipment. A processor may also be implemented as a combination of computing processing units. In this disclosure, terms such as "store," "storage," "data store," "data storage," "database," and substantially any other information storage component associated with the operation and functionality of a component are utilized to refer to a "memory component," an entity embodied in a "memory," or a component that includes a memory. It should be recognized that the memory and / or memory components described herein may be either volatile memory or non-volatile memory, or may include both volatile and non-volatile memory.By way of example, and not limitation, non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable ROM (EEPROM), flash memory, or non-volatile random access memory (RAM) (e.g., ferroelectric RAM (FeRAM)). Volatile memory may include, for example, RAM that may serve as external cache memory. By way of example, and not limitation, RAM is available in many forms, such as synchronous RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), Direct Rambus RAM (DRRAM), Direct Rambus Dynamic RAM (DRDRAM), and Rambus Dynamic RAM (RDRAM). Additionally, the disclosed memory components of the systems or computer-implemented methods herein are intended to include these and any other suitable types of memory, but are not limited to including them.

[0059] What has been described above includes only example systems and computer-implemented methods. Of course, it is not possible to describe every conceivable combination of components or computer-implemented methods for purposes of describing this disclosure, but one of ordinary skill in the art will recognize that many further combinations and permutations of the present disclosure are possible. Furthermore, to the extent that terms such as "includes," "has," "possesses," and the like are used in the detailed description, claims, appendices, and drawings, such terms are intended to be inclusive in the same manner as the term "comprising" is interpreted when used as a transitional term in the claims.

[0060] The descriptions of various embodiments have been presented for illustrative purposes, but are not intended to be exhaustive or limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein has been chosen to best explain the principles of the embodiments, practical applications, or technical improvements to technologies found in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. 1. A quantum converter device comprising: a tuning component including a nonlinear optical material; a microwave resonator; Optical resonators and a first electromagnetic field of the microwave resonator overlaps with a second electromagnetic field of the optical resonator, and the first electromagnetic field and the second electromagnetic field overlap with the nonlinear optical material; The optical resonator interacts with the microwave resonator and the nonlinear optical material based on an input, converting a single optical photon into a single microwave photon through the interaction, the input comprising: a voltage pulse applied to the microwave resonator; or a modulated laser pulse applied to the optical resonator; 1. A quantum converter device comprising:

2. The nonlinear optical material has a non-zero third-order nonlinear susceptibility (χ （３） 10. The quantum converter device of claim 1, comprising a centrosymmetric material having a 3. A quantum converter device as claimed in claim 2, wherein the centrosymmetric material has zero second-order nonlinear susceptibility (χ (2) ), and the input induces a non-zero second-order nonlinear susceptibility (χ (2) ) in the centrosymmetric material.

4. The device of claim 3, wherein the non-zero second-order nonlinear susceptibility (χ (2) ) of the centrosymmetric material is selectively switched on or off based on the voltage pulse.

5. The device of claim 4, wherein the non-zero second-order nonlinear susceptibility (χ (2) ) is selectively switched on by application of the voltage pulse.

6. The device of claim 4 or 5, wherein the non-zero second-order nonlinear susceptibility (χ (2) ) is selectively switched off by removal of the voltage pulse once transformation is complete.

7. The device of claim 4, wherein the induction of the non-zero second-order nonlinear susceptibility (χ (2) ) in the centrosymmetric material causes a π pulse between the optical resonator and the microwave resonator.

8. A device according to any one of claims 2 to 7, wherein the centrosymmetric material comprises silicon and germanium.

9. The nonlinear optical material has a non-zero second-order nonlinear susceptibility (χ （２） 10. The device of claim 1, comprising:

10. A device described in any one of claims 1 to 9, wherein the optical resonator is coupled to a laser.

11. The device of claim 10 , wherein the optical resonator is pumped by the laser, and the laser is gated with a modulator.

12. 12. The device of claim 1, wherein the microwave resonator is coupled to a pulsed voltage source through a switch and an inductor.

13. 1. A quantum converter device comprising: a tuning component including a nonlinear optical material; a microwave resonator; an optical resonator; a first electromagnetic field of the microwave resonator overlaps with a second electromagnetic field of the optical resonator, and the first electromagnetic field and the second electromagnetic field overlap with the nonlinear optical material; The optical resonator interacts with the microwave resonator and the nonlinear optical material based on an input, converting a single microwave photon into a single optical photon through the interaction, the input comprising: a voltage pulse applied to the microwave resonator; or a modulated laser pulse applied to the optical resonator; at least one of: Quantum converter device.

14. The nonlinear optical material has zero second-order nonlinear susceptibility (χ (2) ) and non-zero third-order nonlinear susceptibility (χ （３） 14. The device of claim 13, comprising a centrosymmetric material having a .times. ...

15. The device of claim 14, wherein the non-zero second-order nonlinear susceptibility (χ (2) ) of the centrosymmetric material is selectively switched on or off based on the voltage pulse.

16. The device of claim 15, wherein the non-zero second-order nonlinear susceptibility (χ (2) ) is selectively switched on by application of the voltage pulse, and selectively switched off by removal of the voltage pulse once transformation is complete.

17. A device described in any one of claims 13 to 16, wherein the optical resonator is coupled to a laser, the optical resonator is excited by the laser, and the laser is gated with a modulator.

18. 1. A method comprising: receiving a set of microwave photons with a quantum converter, the quantum converter including a tuning component including a nonlinear optical material, a microwave resonator, and an optical resonator, wherein a first electromagnetic field of the microwave resonator overlaps with a second electromagnetic field of the optical resonator, and the first electromagnetic field and the second electromagnetic field overlap with the nonlinear optical material; the quantum converter receiving an input comprising at least one of a voltage pulse or a modulated laser input, the input causing the optical resonator to interact with the microwave resonator and the nonlinear optical material; the quantum converter converting the set of microwave photons into a single optical photon based on the interaction; and the quantum converter outputs the single optical photon; A method comprising:

19. 1. A method comprising: receiving a set of optical photons with a quantum converter, the quantum converter including a tuning component including a nonlinear optical material, a microwave resonator, and an optical resonator, wherein a first electromagnetic field of the microwave resonator overlaps with a second electromagnetic field of the optical resonator, and the first electromagnetic field and the second electromagnetic field overlap with the nonlinear optical material; the quantum converter receiving an input comprising at least one of a voltage pulse or a modulated laser input, the input causing the optical resonator to interact with the microwave resonator and the nonlinear optical material; the quantum converter converting the set of optical photons into a single microwave photon based on the interaction; and the quantum converter outputs the single microwave photon; A method comprising:

20. The method of claim 18 or 19, wherein the nonlinear optical material comprises a centrosymmetric material with zero second-order nonlinear susceptibility (χ (2) ) and a nonzero third-order nonlinear susceptibility (χ (3) ), and wherein interaction with the input induces a nonzero second-order nonlinear susceptibility (χ (2) ) in the centrosymmetric material.

Images