Photoelectric hybrid integrated high-speed time-frequency domain general zero-beat detector

Abstract

The invention discloses a photoelectric hybrid integrated high-speed time-frequency domain general zero-beat detector, and belongs to the technical field of continuous variable quantum communication. Aiming at the problems that an existing time domain zero-beat detector cannot measure a high repetition frequency pulse signal light field and the integration level of the zero-beat detector is further improved, an optical fiber array, a silicon-based photoelectron chip and a low-noise multi-stage chip amplification circuit are integrated on a ceramic substrate with a low thermal expansion coefficient by adopting a hybrid integration method; the photoelectric hybrid integrated high-speed zero-beat detection chip which is small in size, good in stability and high in measurement precision is developed. And meanwhile, the common-mode rejection ratio of the zero-beat detector to the pulse light field response is optimized by combining the advantages of the chip technology. On the basis, technologies of a chip peripheral power supply circuit, a metal shell, an anti-reflection film and the like are combined, and the photoelectric hybrid integrated high-speed time-frequency domain universal zero-beat detector with the advantages of small size, low power consumption, high precision, good stability, strong anti-interference performance and the like is developed.

Description

Technical Field

[0001] The present invention belongs to the technical field of continuous variable quantum communication, and in particular relates to an optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector. Background Art

[0002] Zero-beat detection devices can measure the orthogonal components of light fields and are widely used in quantum information fields such as quantum communication, quantum tomography, quantum computing, and quantum precision measurement. According to whether the detected signal light field is pulsed or continuous, the detection device can be mainly divided into two types: frequency domain and time domain. Among them, the time domain detection device can directly measure the orthogonal components of the pulse light field without the need to use frequency sideband technology. The advantage of this detection device is that it is compatible with photon counting detection technology and can accurately measure the orthogonal components of the pulse light field with an intensity of the photon number level, but it needs to have a high common mode rejection ratio. With the increase of the pulse repetition frequency, the demand for the common mode rejection ratio of the pulse local oscillator light field will gradually increase. Therefore, this type of detection device cannot realize the measurement of high repetition rate pulse signal light field. The rate was once limited to tens of megahertz, which also caused the continuous variable quantum key distribution technology based on this type of detection device to stagnate.

[0003] Integrating zero-beat detectors can effectively reduce the cost, volume and power consumption of devices, which is conducive to promoting the large-scale application of quantum information technologies such as quantum communication. At present, zero-beat detectors based on integrated detector technology mainly integrate 50 / 50 couplers and germanium silicon photodiodes on silicon, and have not yet integrated the detector's amplifier circuit. In 2024, researchers at the University of Bristol in the UK heterogeneously integrated silicon-based optoelectronic chips and amplifier circuits, and successfully realized zero-beat detection of optoelectronic heterogeneous integration (ABi-CMOS electronic photonic integrated circuit quantum light detector. Sci. Adv. 10, eadk6890 (2024)), but the chip technology threshold is high, and the technology cannot be realized in China in a short time. Summary of the invention

[0004] In view of the problem that the existing time-domain zero-beat detectors are unable to measure the high-repetition-rate pulse signal light field, and in order to further improve the integration of the zero-beat detector, the present invention provides a high-speed time-frequency domain universal zero-beat detector with optoelectronic hybrid integration. The detector improves the common-mode rejection ratio and other aspects of the traditional frequency-domain balanced zero-beat detector, and adopts the technology of interference between the pulse signal light field and the continuous local oscillator light field. It can detect the orthogonal components of the pulse signal light with an intensity at the level of photons, and can also detect the orthogonal components of the continuous signal light with frequency sideband modulation of the amplitude and phase. The core of the detector is an optoelectronic hybrid integrated chip. During use, after the detector is powered on, it only needs to introduce the signal light and the local oscillator light to be measured into the optoelectronic hybrid integrated chip through a commercial optical fiber interface, and then the electrical signal containing the information of the orthogonal components of the signal light can be output. It is usually connected to an oscilloscope or a radio frequency spectrum analyzer for measurement.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A high-speed time-frequency domain universal zero-beat detector with optoelectronic hybrid integration, the structure of which includes an optical fiber array, an optoelectronic hybrid integrated chip, a peripheral power supply circuit, a metal shell and an anti-reflection film;

[0007] The optical fiber array includes a first high numerical aperture polarization-maintaining optical fiber and a second high numerical aperture polarization-maintaining optical fiber, and the optical fiber ports are a first commercial optical fiber interface and a second commercial optical fiber interface;

[0008] The optical fiber array and the optoelectronic hybrid integrated chip are packaged and connected in an end-face coupling manner to guide the signal light and the local oscillator light into the optoelectronic hybrid integrated chip;

[0009] The optoelectronic hybrid integrated chip has a universal zero-beat detector function in the time and frequency domains;

[0010] The peripheral power supply circuit provides an adjustable bias voltage and a low-noise power supply voltage for the optoelectronic hybrid integrated chip. The overall power supply interface of the circuit needs to be connected to an external shielded cable, and a radio frequency interface is used to output electrical signals.

[0011] The entire detector is placed in a metal shell with good shielding properties, and the inner wall of the metal shell is covered with an anti-reflection film.

[0012] Furthermore, the optoelectronic hybrid integrated chip is composed of a silicon-based optoelectronic chip and a multi-stage chip amplifier circuit packaged on a low thermal expansion coefficient ceramic substrate;

[0013] Furthermore, the silicon-based optoelectronic chip is fixed on a low thermal expansion coefficient ceramic substrate using silver glue with good thermal conductivity, which is beneficial to heat dissipation; grooves are designed on the low thermal expansion coefficient ceramic substrate to prevent the diffusion of silver glue and refractive index matching glue. The electronic components such as the micro-amplifier chip, chip resistor, chip capacitor and chip inductor in the multi-stage chip amplifier circuit are soldered in the surface circuit of the low thermal expansion coefficient ceramic substrate by flip-chip welding. The use of micro-chip electronic components in the multi-stage amplifier circuit as a whole is beneficial to reducing the circuit volume, improving impedance matching performance and realizing high-bandwidth zero-beat detection; when the optical fiber array is end-face coupled with the silicon-based optoelectronic chip, the gap is filled with refractive index matching glue to reduce coupling loss;

[0014] The optical fiber array is attached to a ceramic substrate with a low thermal expansion coefficient and is reinforced with ultraviolet glue with a small thermal expansion coefficient, so as to stabilize coupling loss.

[0015] Furthermore, the silicon-based optoelectronic chip contains an end face array coupling structure, a 2×2 50 / 50 multimode coupler, a first attenuator, a second attenuator, a first germanium silicon photodiode and a second germanium silicon photodiode in cascade; after the signal light and the local oscillator light enter the silicon-based optoelectronic chip through the end face array coupling structure, they are coupled in the 2×2 50 / 50 multimode coupler, and the output coupling light is incident on the first germanium silicon photodiode and the second germanium silicon photodiode in cascade after passing through the first attenuator and the second attenuator respectively. The pads of the silicon-based optoelectronic chip are connected to the pads in the surface circuit of the low thermal expansion coefficient ceramic substrate by gold wire bonding.

[0016] The input and output optical paths of the 2×2 50 / 50 multimode coupler in the silicon-based optoelectronic chip adopt a symmetrical structure, and the first attenuator and the second attenuator and the cascaded first germanium silicon photodiode and the second germanium silicon photodiode adopt the same structure to improve the consistency of the light response to the pulse signal; the bias voltage of the cascaded first germanium silicon photodiode and the second germanium silicon photodiode is adjustable to compensate for the response difference of the photodiodes.

[0017] The common end of the pre-stage amplifier circuit and the first germanium silicon photodiode and the second germanium silicon photodiode in the multi-stage chip amplifier circuit is directly bonded with gold wire to improve the impedance matching characteristics of the circuit; the pre-stage and post-stage amplifier circuits use capacitor coupling to avoid post-stage amplification of the DC component, which may cause saturation of the detector.

[0018] The present invention adopts a series of technologies to improve the response of the zero-beat detector to pulse signal light, including unifying the input local oscillator light into continuous light, avoiding the need for extremely high common mode rejection ratio for high-intensity pulsed local oscillator light; changing the type of multi-stage amplification circuit from a charge amplifier to a transimpedance amplifier or a radio frequency amplifier, avoiding the limitation of the charge amplifier requiring input pulse light, and improving the response bandwidth of the detector;

[0019] The first attenuator and the second attenuator in the silicon-based optoelectronic chip can flexibly select a thermally adjustable MZ structure or a PIN structure. The former performs attenuation based on the MZ interference principle, and the latter performs attenuation based on the carrier absorption principle.

[0020] When the optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector measures the pulse signal light, the time width of the pulse signal light needs to be less than the inverse of the detector bandwidth, that is, the zero-beat detector can linearly respond to the pulse light after the pulse signal light interferes with the continuous local oscillator light; in order to accurately obtain the orthogonal components of the pulse signal light, it is necessary to fully collect the pulse current signal output by the zero-beat detector, and then perform numerical integration. After the integral value is normalized according to the shot noise, the orthogonal component value of the pulse signal light field can be accurately obtained.

[0021] When the optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector measures the amplitude and phase of continuous signal light modulated by frequency sidebands, the measurement results need to be mixed and filtered to obtain the orthogonal components of the signal light field.

[0022] When the optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector is used and the power is turned on, it is only necessary to introduce the signal light and local oscillator light to be measured into the optoelectronic hybrid integrated chip through a commercial optical fiber interface, and use a radio frequency interface to output an electrical signal containing the orthogonal component information of the signal light, and the electrical signal is measured on an oscilloscope or a radio frequency spectrum analyzer.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] 1. The present invention adopts optoelectronic hybrid integration technology to integrate silicon-based optoelectronic chips with amplifier chips, resistors, inductors and capacitor chips, etc., further reducing the size of the core components of the zero-beat detector, and has the advantages of small size, low power consumption, low cost and high precision.

[0025] 2. The detector in the present invention has made innovative improvements in the common mode rejection ratio characteristics of traditional frequency domain zero-beat detectors. Combining the advantages of the chip's own technology, it uses consistent GeSi photodiodes, improved optical path symmetry, adjustable bias voltage and other technologies to optimize the common mode rejection ratio of the zero-beat detector in response to the pulse light field. It can measure both pulse signal light and continuous signal light. It uses the technology of interference between pulse signal light field and continuous local oscillator light field to successfully solve the measurement problem of high repetition rate pulse signal light field, breaking through the bottleneck of traditional pulse signal light zero-beat detection.

[0026] 3. The detector in the present invention adopts a metal shell with an anti-reflection film inside the shell, adopts a power interface and power line with good shielding properties, and the output interface is a coaxial radio frequency interface, which improves the anti-interference characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0028] Figure 2 This is a schematic diagram of the structure of the optoelectronic hybrid integrated chip of the present invention;

[0029] Figure 3 This is a schematic diagram of the structure of the silicon-based optoelectronic chip of the present invention;

[0030] Figure 4 The results of the optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector described in the present invention measured by a radio frequency spectrum analyzer at different local oscillator light powers within a bandwidth of 0-300MHz when the signal light field is a vacuum field and the local oscillator light is a continuous light;

[0031] Figure 5 The results of the optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector described in the present invention measured by an oscilloscope at different local oscillator light powers when the signal light field is a vacuum field and the local oscillator light is a continuous light;

[0032] Figure 6 The linear response test results of the optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector described in the present invention;

[0033] Figure 7 It is a trajectory diagram of the pulse photovoltage signal output by the optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector described in the present invention when the signal light is a pulse light field, the local oscillator light is a continuous light field, and the phase is a random phase.

[0034] Figure numerals: 1. optical fiber array; 2. optoelectronic hybrid integrated chip; 3. peripheral power supply circuit; 4. metal shell; 5. anti-reflection film; 6. first high numerical aperture polarization-maintaining optical fiber; 7. second high numerical aperture polarization-maintaining optical fiber; 8. first commercial optical fiber interface; 9. second commercial optical fiber interface; 10. overall power supply interface of the circuit; 11. shielded cable; 12. radio frequency interface; 13. low thermal expansion coefficient ceramic substrate; 14. silicon-based optoelectronic chip; 15. multi-stage chip amplifier circuit; 16. groove of low thermal expansion coefficient ceramic substrate; 17. end face array coupling structure; 18. 2×2 50 / 50 multimode coupler; 19. first attenuator; 20. second attenuator; 21. first germanium silicon photodiode; 22. second germanium silicon photodiode. DETAILED DESCRIPTION

[0035] In order to gain a deeper understanding of the present invention, we will provide a comprehensive and detailed description of the present invention. However, the present invention has multiple implementations and is not limited to the specific examples listed herein. The presentation of these examples is intended to deepen the comprehensive understanding of the disclosure of the present invention.

[0036] A photoelectric hybrid integrated high-speed time-frequency domain universal zero-beat detector, the structure of which includes an optical fiber array 1, a photoelectric hybrid integrated chip 2, a peripheral power supply circuit 3, a metal shell 4 and an anti-reflection film 5;

[0037] The optical fiber array 1 contains a first high numerical aperture polarization-maintaining optical fiber 6 and a second high numerical aperture polarization-maintaining optical fiber 7, and the optical fiber ports are a first commercial optical fiber interface 8 and a second commercial optical fiber interface 9; the specific type is an FC / APC interface; the optical fiber array 1 and the optoelectronic hybrid integrated chip 2 are packaged and connected in an end-face coupling manner to introduce signal light and local oscillator light into the optoelectronic hybrid integrated chip 2; the optoelectronic hybrid integrated chip 2 has a universal zero-beat detector function in the time-frequency domain;

[0038] The peripheral power supply circuit 3 provides an adjustable bias voltage and a low-noise power supply voltage for the optoelectronic hybrid integrated chip 2. The overall power supply interface 10 of the circuit needs to be externally connected to a shielded cable 11 to reduce interference from various electromagnetic signals. The radio frequency interface 12 is used to output electrical signals.

[0039] The entire detector is placed in a metal shell 4 with good shielding properties. The inner wall of the metal shell 4 is affixed with an anti-reflection film 5, which has excellent broadband absorption performance for electromagnetic waves incident at both vertical and oblique angles.

[0040] Furthermore, the optoelectronic hybrid integrated chip 2 is composed of a silicon-based optoelectronic chip 14 and a multi-stage chip amplifier circuit 15 packaged on a low thermal expansion coefficient ceramic substrate 13; the silicon-based optoelectronic chip 14 is fixed on the low thermal expansion coefficient ceramic substrate 13 by using silver glue with good thermal conductivity, which is beneficial to heat dissipation; the electronic components such as the micro-amplifier chip, chip resistor, chip capacitor and chip inductor in the multi-stage chip amplifier circuit 15 are welded in the surface circuit of the low thermal expansion coefficient ceramic substrate 13 by flip-chip welding. The use of micro-chip electronic components in the multi-stage amplifier circuit as a whole is beneficial to reducing the circuit volume, improving impedance matching performance and realizing high-bandwidth zero-beat detection; the low thermal expansion coefficient ceramic substrate 13 is designed with a groove 16 to prevent the diffusion of silver glue and refractive index matching glue. The low thermal expansion coefficient ceramic substrate is made of aluminum nitride with a thermal expansion coefficient of about 4-5ppm / ℃. When the optical fiber array 1 is end-face coupled with the silicon-based optoelectronic chip 14, the gap is filled with refractive index matching glue to reduce coupling loss; the optical fiber array 1 is attached to the low thermal expansion coefficient ceramic substrate 13 and reinforced with ultraviolet glue with a small thermal expansion coefficient to stabilize coupling loss. The refractive index matching glue has strong fluidity and can well fill the gap between the optical fiber array and the silicon-based optoelectronic chip; the ultraviolet glue with a small thermal expansion coefficient has extremely poor fluidity and can prevent the displacement of the optical fiber array; the silicon-based optoelectronic chip is designed by us and manufactured by Chongqing United Microelectronics Center Co., Ltd. (CUMEC); the low thermal expansion coefficient ceramic substrate is designed by us and manufactured by Xi'an Leiguang Optoelectronic Technology Co., Ltd.

[0041] The process of end-face coupling packaging of the optical fiber array and the silicon-based optoelectronic chip is implemented by the following technical solution: the output port of the optical fiber array and the input port of the silicon-based optoelectronic chip are aligned using a precision alignment coupling system. When the coupling loss reaches the theoretical value, the alignment coupling is successful. At this time, the robot arm is controlled to lift the optical fiber array upward by 5um, and a UV glue with a small thermal expansion coefficient is applied at the corresponding position directly below the optical fiber array on the low thermal expansion coefficient ceramic substrate. Then, the robot arm is controlled to vertically lower the optical fiber array by 5um to make the optical fiber array contact with the UV glue with a small thermal expansion coefficient. The precision alignment coupling system is used for alignment again. When the coupling loss reaches the theoretical value, the alignment coupling is successful. At this time, a refractive index matching glue is applied at the gap between the optical fiber array and the silicon-based optoelectronic chip. The refractive index matching glue naturally flows to fill the gap, and the coupling loss is reduced. The UV glue with a small thermal expansion coefficient and the refractive index matching glue are both cured by ultraviolet light irradiation, and the UV intensity is set to 400mW / cm 2 , irradiation distance 5cm, curing time 120S; during curing, irradiate the refractive index matching glue first, and after the refractive index matching glue is completely cured, irradiate and cure the UV glue with a small thermal expansion coefficient under the optical fiber array to minimize the impact of the UV curing process on the coupling loss.

[0042] The silicon-based optoelectronic chip 14 includes an end face array coupling structure 17, a 2×2 50 / 50 multimode coupler 18, a first attenuator 19, a second attenuator 20, a first germanium silicon photodiode 21 and a second germanium silicon photodiode 22 in cascade; after the signal light and the local oscillator light enter the silicon-based optoelectronic chip 14 through the end face array coupling structure 17, they are coupled in the 2×2 50 / 50 multimode coupler 18, and the output coupled light is incident on the first germanium silicon photodiode 21 and the second germanium silicon photodiode 22 in cascade after passing through the first attenuator 19 and the second attenuator 20 respectively. The pads of the silicon-based optoelectronic chip are connected to the pads in the surface circuit of the low thermal expansion coefficient ceramic substrate by gold wire bonding.

[0043] Furthermore, the common end of the pre-stage amplifier circuit in the multi-stage chip amplifier circuit 15 and the first germanium silicon photodiode 21 and the second germanium silicon photodiode 22 connected in series are directly bonded with gold wire to improve the impedance matching characteristics of the circuit; the pre-stage and post-stage amplifier circuits need to adopt capacitive coupling to avoid post-stage amplification of the DC component, which may cause saturation of the detector.

[0044] The input and output optical paths of the 2×2 50 / 50 multimode coupler 18 in the silicon-based optoelectronic chip 14 adopt a symmetrical structure, and the first attenuator 19 and the second attenuator 20 and the cascaded first germanium silicon photodiode 21 and the second germanium silicon photodiode 22 adopt the same structure to improve the consistency of the light response to the pulse signal; the bias voltage of the cascaded first germanium silicon photodiode 21 and the second germanium silicon photodiode 22 is adjustable to compensate for the difference in photodiode response.

[0045] The first attenuator 19 and the second attenuator 20 in the silicon-based optoelectronic chip 14 can flexibly select a thermally adjustable MZ structure or a PIN structure. The former performs attenuation based on the MZ interference principle, and the latter performs attenuation based on the carrier absorption principle.

[0046] When the optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector measures the pulse signal light, the time width of the pulse signal light needs to be less than the inverse of the detector bandwidth, that is, the zero-beat detector can linearly respond to the pulse light after the pulse signal light interferes with the continuous local oscillator light; in order to accurately obtain the orthogonal components of the pulse signal light, it is necessary to fully collect the pulse current signal output by the zero-beat detector, and then perform numerical integration. After the integral value is normalized according to the shot noise, the orthogonal component value of the pulse signal light field can be accurately obtained.

[0047] When the optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector measures the amplitude and phase of continuous signal light modulated by frequency sidebands, the measurement results need to be mixed and filtered to obtain the orthogonal components of the signal light field.

[0048] When the optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector is used and the power is turned on, it is only necessary to introduce the signal light and local oscillator light to be measured into the optoelectronic hybrid integrated chip 2 through a commercial optical fiber interface, and use the radio frequency interface 12 to output an electrical signal containing the orthogonal component information of the signal light, and the electrical signal is measured on an oscilloscope or a radio frequency spectrum analyzer.

[0049] Figure 1 The figure shows a schematic diagram of the overall structure of the present invention. The optical fiber array and the optoelectronic hybrid integrated chip are packaged and connected by end-face coupling to introduce the signal light and the local oscillator light into the optoelectronic hybrid integrated chip. The peripheral power supply circuit provides an adjustable bias voltage and a low-noise power supply voltage for the optoelectronic hybrid integrated chip. The overall power supply interface of the circuit needs to be connected to an external shielded cable to reduce interference from various electromagnetic signals, and a radio frequency interface is used to output electrical signals. The entire detector is placed in a well-shielded metal shell, and the inner wall of the metal shell is affixed with an anti-reflection film.

[0050] Figure 2 The figure shows a schematic diagram of the structure of the optoelectronic hybrid integrated chip described in the present invention. The optoelectronic hybrid integrated chip is composed of a silicon-based optoelectronic chip and a multi-stage chip amplifier circuit packaged on a low thermal expansion coefficient ceramic substrate. Grooves are designed on the low thermal expansion coefficient ceramic substrate to prevent the diffusion of silver glue and refractive index matching glue; the material of the low thermal expansion coefficient ceramic substrate is aluminum nitride, and the thermal expansion coefficient is about 4-5ppm / ℃, which can minimize the change in coupling loss caused by thermal expansion of the substrate material during UV curing. The pads of the silicon-based optoelectronic chip are connected to the pads in the surface circuit of the low thermal expansion coefficient ceramic substrate by gold wire bonding.

[0051] Figure 3 The figure shows a schematic diagram of the structure of the silicon-based optoelectronic chip of the present invention. The silicon-based optoelectronic chip contains an end face array coupling structure, a 2×2 50 / 50 multimode coupler, a first attenuator, a second attenuator, a first germanium silicon photodiode and a second germanium silicon photodiode in cascade. After the signal light and the local oscillator light enter the silicon-based optoelectronic chip through the end face array coupling structure, they are coupled in the 2×2 50 / 50 multimode coupler, and the output coupled light is incident on the first germanium silicon photodiode and the second germanium silicon photodiode in cascade after passing through the first attenuator and the second attenuator.

[0052] Figure 4 The figure shows the results of the optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector of the present invention measured by a radio frequency spectrum analyzer at different local oscillator light powers when the signal light field is a vacuum field and the local oscillator light is a continuous light. The instrument used to collect the waveform is the radio frequency spectrum analyzer KEYSIGHT N9030B.

[0053] Figure 5The figure shows the results of the optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector of the present invention measured by an oscilloscope at different local oscillator light powers when the signal light field is a vacuum field and the local oscillator light is a continuous light. The instrument used to collect the waveform is an oscilloscope Tektronix MSO 5204B.

[0054] Figure 6 The figure shows the linear response test result of the optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector of the present invention. It is obvious that the detector has good linear response characteristics.

[0055] Figure 7 The figure shows the trajectory of the pulse light voltage signal output by the detector of the optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector described in the present invention when the signal light is a pulse light field, the local oscillator light is a continuous light field, and the phase is a random phase. The specific test process is: after the laser emits light, an amplitude modulator is used to modulate the pulse light with a high extinction ratio, and then the phase modulator performs random phase modulation on the pulse light to generate a pulse signal light field with a pulse width of 5ns. After the pulse signal light field and the continuous local oscillator light field enter the silicon-based optoelectronic chip through the end face array coupling structure, they are coupled in a 2×2 50 / 50 multimode coupler. The output coupling light is incident on the first germanium silicon photodiode and the second germanium silicon photodiode in cascade after passing through the first attenuator and the second attenuator, and the output signal is amplified by the low-noise multi-stage chip amplifier circuit and output by the radio frequency interface. The instrument used to collect the waveform is the oscilloscope Tektronix MSO 5204B. It can be seen from the figure that the pulse signal light field can interfere well with the continuous local oscillator light field.

[0056] The contents not described in detail in the specification of the present invention belong to the prior art known to the professional and technical personnel in the field. Although the illustrative specific embodiments of the present invention are described above to facilitate the understanding of the present invention by the technical personnel in the field, it should be clear that the present invention is not limited to the scope of the specific embodiments. For the ordinary technical personnel in the field, as long as various changes are within the spirit and scope of the present invention defined and determined by the attached claims, these changes are obvious, and all inventions and creations using the concept of the present invention are protected.

Claims

1. A high-speed time-frequency domain universal zero-beat detector with optoelectronic hybrid integration, characterized in that: Its structure includes an optical fiber array (1), an optoelectronic hybrid integrated chip (2), a peripheral power supply circuit (3), a metal shell (4) and an anti-reflection film (5); The optical fiber array (1) contains a first high numerical aperture polarization-maintaining optical fiber (6) and a second high numerical aperture polarization-maintaining optical fiber (7), and the optical fiber ports are a first commercial optical fiber interface (8) and a second commercial optical fiber interface (9); The optical fiber array (1) and the optoelectronic hybrid integrated chip (2) are packaged and connected in an end-face coupling manner, so that the signal light and the local oscillator light are introduced into the optoelectronic hybrid integrated chip (2); The optoelectronic hybrid integrated chip (2) has a universal zero-beat detector function in the time and frequency domains; The peripheral power supply circuit (3) provides an adjustable bias voltage and a low-noise power supply voltage for the optoelectronic hybrid integrated chip (2); the overall power supply interface (10) of the circuit needs to be externally connected to a shielded cable (11), and a radio frequency interface (12) is used to output electrical signals; The entire detector is placed in a metal shell (4) with good shielding properties, and an anti-reflection film (5) is attached to the inner wall of the metal shell (4).

2. A high-speed time-frequency domain universal zero-beat detector of optoelectronic hybrid integration according to claim 1, characterized in that: The optoelectronic hybrid integrated chip (2) is composed of a silicon-based optoelectronic chip (14) and a multi-stage chip amplifier circuit (15) packaged on a low thermal expansion coefficient ceramic substrate (13); The silicon-based optoelectronic chip (14) is fixed on a low thermal expansion coefficient ceramic substrate (13) using silver glue; The electronic components in the multi-stage chip amplifier circuit (15) are soldered in a surface circuit of a low thermal expansion coefficient ceramic substrate (13) by flip-chip soldering; The low thermal expansion coefficient ceramic substrate (13) is designed with a groove (16) to prevent the silver glue and the refractive index matching glue from diffusing.

3. A high-speed time-frequency domain universal zero-beat detector of optoelectronic hybrid integration according to claim 2, characterized in that: The silicon-based optoelectronic chip (14) contains an end face array coupling structure (17), a 2×2 50 / 50 multimode coupler (18), a first attenuator (19), a second attenuator (20), a first germanium silicon photodiode (21) and a second germanium silicon photodiode (22) connected in cascade; after the signal light and the local oscillation light enter the silicon-based optoelectronic chip (14) through the end face array coupling structure (17), they are coupled in the 2×2 50 / 50 multimode coupler (18), and the output coupled light is incident on the first germanium silicon photodiode (21) and the second germanium silicon photodiode (22) connected in cascade after passing through the first attenuator (19) and the second attenuator (20).

4. A high-speed time-frequency domain universal zero-beat detector of optoelectronic hybrid integration according to claim 3, characterized in that: The input and output optical paths of the 2×2 50 / 50 multimode coupler (18) in the silicon-based optoelectronic chip (14) adopt a symmetrical structure; the first attenuator (19) and the second attenuator (20) and the cascaded first germanium silicon photodiode (21) and the second germanium silicon photodiode (22) adopt the same structure, thereby improving the consistency of the response to the pulse signal light; the bias voltage of the cascaded first germanium silicon photodiode (21) and the second germanium silicon photodiode (22) is adjustable, so as to compensate for the response difference of the photodiodes.

5. A high-speed time-frequency domain universal zero-beat detector of optoelectronic hybrid integration according to claim 4, characterized in that: When the optical fiber array (1) and the silicon-based optoelectronic chip (14) are end-face coupled, the gap between them is filled with a refractive index matching glue; The optical fiber array (1) is attached to a ceramic substrate (13) with a low thermal expansion coefficient and is reinforced with ultraviolet glue with a low thermal expansion coefficient; The pad of the silicon-based optoelectronic chip (14) is connected to the pad in the surface circuit of the low thermal expansion coefficient ceramic substrate (13) by gold wire bonding; The common end of the pre-stage amplifier circuit in the multi-stage chip amplifier circuit (15) and the first germanium silicon photodiode (21) and the second germanium silicon photodiode (22) connected in cascade are directly bonded with gold wires to improve the impedance matching characteristics of the circuit; The front and rear stage amplifier circuits in the multi-stage chip amplifier circuit (15) adopt capacitor coupling to avoid performing rear stage amplification on the DC component, which would cause saturation of the detector.

6. A high-speed time-frequency domain universal zero-beat detector of optoelectronic hybrid integration according to claim 5, characterized in that: The first attenuator (19) and the second attenuator (20) in the silicon-based optoelectronic chip (14) are thermally adjustable MZ structures or PIN structures.

7. A high-speed time-frequency domain universal zero-beat detector of optoelectronic hybrid integration according to claim 6, characterized in that: When the detector measures the pulse signal light, the time width of the pulse signal light needs to be smaller than the inverse of the detector bandwidth, that is, the zero-beat detector can linearly respond to the pulse light after the pulse signal light interferes with the continuous local oscillator light.

8. The optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector according to claim 7, characterized in that: When the detector measures the amplitude and phase of the continuous signal light modulated by the frequency sideband, it is necessary to mix and filter the measurement results to obtain the orthogonal components of the signal light field.

9. The optoelectronic hybrid integrated high-speed time-frequency domain universal zero-beat detector according to claim 8, characterized in that: When the detector is used and the power supply is turned on, it is only necessary to introduce the signal light and local oscillator light to be measured into the optoelectronic hybrid integrated chip (2) through a commercial optical fiber interface, and use the radio frequency interface (12) to output an electrical signal containing information on the orthogonal components of the signal light, and the electrical signal is measured on an oscilloscope or a radio frequency spectrum analyzer.

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