High-sensitivity quantum sensing light quantum chip and setting method and application thereof

Abstract

The invention discloses a high-sensitivity quantum sensing light quantum chip and a setting method and application thereof, and belongs to the technical field of sensors. The light quantum chip provided by the invention comprises a quantum light source module, a phase sensing interference module and an adjustable reflection module which are connected in sequence. The light quantum chip provided by the invention has relatively high sensitivity and a relatively wide application range. The invention further provides a setting method and application of the light quantum chip.

Description

Technical Field

[0001] The present invention relates to the field of sensor technology, and in particular to a high-sensitivity quantum sensing photon chip and a setting method and application thereof. Background Art

[0002] The accuracy of the interferometer using classical lasers is limited by the classical shot noise. According to the central limit theorem, after N times (N is much greater than 1) of independent measurement, the measurement results satisfy the normal distribution, and the measurement error can reach 1 / √N. This proportionality factor is the standard quantum limit. Quantum precision measurement can use the interaction between particles to surpass this limit. After N particles are entangled with each other as measurement resources, the measurement accuracy can be improved to 1 / N, which is called the Heisenberg Limit. The resource state of quantum precision measurement is usually a compressed state or a photon number entangled state N00N state. The latter represents the superposition of two situations where N photons are both in path 1 and in path 2. When using the N00N state for phase measurement, one of the paths is added to the phase to be measured, and the last two paths are interfered; since N photons all pass through the phase to be measured, the final selection of a suitable interference device can reflect the sensitivity of the N-fold phase. The methods for generating multi-photon entanglement usually include the generation of photon pairs by nonlinear processes and multi-photon interaction logic gates; among them, the nonlinear processes include atomic cascade transitions, optical parametric down-conversion processes in second-order nonlinear crystals, four-wave mixing processes in silicon or optical fibers, etc.; multi-photon interaction logic gates include fusion operations and controlled phase gates, etc.; by using two methods for generating multi-photon entanglement, many bulk optical experiments have been reported. Photonic quantum chips made of silicon, silicon nitride, lithium niobate, etc. as substrates are emerging technologies. Their emergence overcomes the problem of large space occupied by bulk optics and can integrate thousands of optical components on millimeter-level chips; gratings guide the input and output of light, optical waveguides guide the propagation of light, and the phase generated by the photons moving in the waveguide has high stability. Compared with other types of chips, the manufacturing process of silicon-based electronic chips is relatively complete and has been scaled and industrialized. Silicon-based optical chips have higher process precision and are easier to implement than chips made of other materials. In the silicon-based four-wave mixing process, two pump photons annihilate to produce a pair of conversion photons that satisfy the laws of conservation of energy and momentum, called signal photons and idle photons respectively. In the degenerate four-wave mixing process, two pump photons of different frequencies annihilate to produce a photon pair of the same frequency.

[0003] However, current experiments have only achieved quantum precision measurement of four photons. It is difficult to expand traditional methods to precision measurements with more photons and higher accuracy. There is still a lack of a high sensing multiple, configurable, and easy-to-implement solution. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a highly sensitive quantum sensing photon chip, which can effectively improve the stability, resolution and precision of detection; and the photon chip provided by the present invention has a high degree of integration and can realize multi-parameter sensing.

[0005] The present invention also provides a method for setting up the above-mentioned photon chip.

[0006] The present invention also provides applications of the above-mentioned photon quantum chip.

[0007] According to an embodiment of the first aspect of the present invention, a high-sensitivity quantum sensing photon chip is provided, wherein the photon chip comprises a quantum light source module, a phase sensing interference module and an adjustable reflection module which are sequentially connected.

[0008] The control method according to the embodiment of the present invention has at least the following beneficial effects:

[0009] The optical quantum chip provided by the present invention is provided with an adjustable reflection module, so that photons can pass through the phase sensing interference module back and forth, thereby achieving a high phase accuracy (compared with not providing the adjustable reflection module).

[0010] The photonic quantum chip provided by the present invention utilizes integrated optical technology and integrates three modules, thereby improving the scalability, integration, stability, etc. of multi-photon precision measurement experiments; it also has the characteristics of high integration, high spatial resolution, and multi-parameter sensing.

[0011] According to some embodiments of the present invention, the quantum light source module comprises:

[0012] The first Mach-Zehnder interferometer;

[0013] A phase shifter, the phase shifter is connected to an optical path exit of the first Mach-Zehnder interferometer;

[0014] a waveguide, wherein the waveguide is connected to the phase shifter;

[0015] A second Mach-Zehnder interferometer and a third Mach-Zehnder interferometer are arranged in parallel and connected to the waveguide.

[0016] Among them, the first Mach-Zehnder interferometer plays the role of a beam splitter, which can divide the classical pump light into two paths with equal amplitudes; the phase shifter and the waveguide have the role of a collinear nonlinear light source, and a degenerate spontaneous four-wave mixing process or a spontaneous parametric down-conversion process occurs. The two paths of light generated by the beam splitter generate photon pairs in this step to realize a superposition photon source; the second Mach-Zehnder interferometer and the third Mach-Zehnder interferometer have the role of a pump filter, in which the pump light is filtered out, and the converted photons enter the phase sensing interference module, thereby realizing the separation of the pump light and the converted photons; after the three are combined, a four-wave mixing or spontaneous parametric down-conversion quantum light source can be obtained, and a superposition state of 2, 4 or 6 photon paths can be prepared; even if the adjustable reflection module is turned off, the optical quantum chip provided by the present invention can still measure a state with 6 times the phase accuracy; after the adjustable reflection module is turned on, the phase sensing accuracy (sensitivity) of the optical quantum chip provided by the present invention can reach up to 12 times, and at the same time, a sensing sensitivity of 4 times or 8 times can be achieved.

[0017] According to some embodiments of the present invention, the quantum light source module further includes an input optical fiber and a grating; wherein the classical laser passes through the input optical fiber and the grating in sequence and is then split by the first Mach-Zehnder interferometer.

[0018] According to some embodiments of the present invention, the quantum light source module further includes a first intermediate light path connected in parallel with the phase shifter and connected to another light path exit of the first Mach-Zehnder interferometer. It can be understood that the first intermediate light path is connected to the waveguide. That is, one of the two paths of light separated from the first Mach-Zehnder interferometer enters the phase shifter, and the other enters the first intermediate light path.

[0019] According to some embodiments of the present invention, the quantum light source module further includes a fourth Mach-Zehnder interferometer and a fifth Mach-Zehnder interferometer which are arranged in parallel between the first Mach-Zehnder interferometer and the waveguide.

[0020] The fourth Mach-Zehnder interferometer is arranged between the phase shifter and the waveguide. Specifically, an optical path inlet of the fourth Mach-Zehnder interferometer is connected to the phase shifter, and an optical path outlet is connected to the waveguide.

[0021] The fifth Mach-Zehnder interferometer is arranged between the first intermediate optical path and the waveguide. Specifically, an optical path inlet of the fifth Mach-Zehnder interferometer is connected to the first intermediate optical path, and an optical path outlet is connected to the waveguide.

[0022] According to some embodiments of the present invention, the fourth Mach-Zehnder interferometer and the fifth Mach-Zehnder interferometer are unequal-arm Mach-Zehnder interferometers.

[0023] According to some embodiments of the present invention, the waveguide is at least one of a straight spiral waveguide or a microring resonator, wherein the straight spiral waveguide refers to a straight waveguide rolled into a spiral shape, and its function is to generate a nonlinear process to realize a multi-photon source.

[0024] According to some embodiments of the present invention, the second Mach-Zehnder interferometer and the third Mach-Zehnder interferometer are unequal-arm Mach-Zehnder interferometers.

[0025] According to some embodiments of the present invention, the optical quantum chip further includes a first output optical fiber connected to the fourth Mach-Zehnder interferometer.

[0026] According to some embodiments of the present invention, the quantum light source module further comprises a first output waveguide connecting the fourth Mach-Zehnder interferometer and the first output optical fiber. It is understandable that a filter is provided between the first output waveguide and the first output optical fiber.

[0027] According to some embodiments of the present invention, the optical quantum chip further includes a second output optical fiber connected to the fifth Mach-Zehnder interferometer.

[0028] According to some embodiments of the present invention, the quantum light source module further comprises a second output waveguide connecting the fifth Mach-Zehnder interferometer and the second output optical fiber. It is understandable that a filter is provided between the second output optical fiber and the second output waveguide.

[0029] According to some embodiments of the present invention, the phase sensing interference module includes a first multimode interferometer, a phase shifter to be measured, a second multimode interferometer and a bias phase shifter which are sequentially connected to the quantum light source module.

[0030] According to some embodiments of the present invention, the phase sensing interference module further includes a second intermediate optical path connected to the first multimode interferometer and connected in parallel with the phase shifter to be measured. That is, in actual applications, the two optical paths formed by the beam splitting connected by the first multimode interferometer respectively pass through the phase shifter to be measured and the second intermediate optical path before entering the second multimode interferometer.

[0031] According to some embodiments of the present invention, the first multi-mode interferometer and the second multi-mode interferometer are 50:50 interferometers, that is, the two separated light beams are equal.

[0032] According to some embodiments of the present invention, the phase sensing interference module further includes a third intermediate optical path arranged in parallel with the bias phase shifter. That is, in practical applications, the two paths of light generated by the second multimode interferometer beam splitting are transmitted through the bias phase shifter and the third intermediate optical path respectively.

[0033] According to some embodiments of the present invention, the adjustable reflection module includes a first tail end connected to the Mach-Zehnder interferometer and a second tail end connected to the Mach-Zehnder interferometer connected to the phase sensing interference module; and a first photon outlet connected to the Mach-Zehnder interferometer connected to the first tail end, and a second photon outlet connected to the Mach-Zehnder interferometer connected to the second tail end. The two exit ends of the Mach-Zehnder interferometer connected to the first tail end and the Mach-Zehnder interferometer connected to the second tail end are connected, thereby forming a light loop and realizing the reflection of photons.

[0034] According to some embodiments of the present invention, the first photon outlet is connected to the first tail-end connected Mach-Zehnder interferometer, and the second photon outlet is connected to the second tail-end connected Mach-Zehnder interferometer. In actual production, if the first tail-end connected Mach-Zehnder interferometer and the second tail-end connected Mach-Zehnder interferometer are turned off and do not work, the photon is output from the first photon outlet and / or the second photon outlet. Detecting the |1,1> item of the output state can achieve 2-fold phase induction; detecting the |1,3> or |3,1> item of the output state can achieve 4-fold phase induction; detecting the |3,3> item of the output state can obtain a 6-fold phase induction curve.

[0035] If the first tail-end connected Mach-Zehnder interferometer and the second tail-end connected Mach-Zehnder interferometer work, the photon returns to the phase sensing interference module along the original path, and finally outputs from the fourth Mach-Zehnder interferometer and the fifth Mach-Zehnder interferometer of the quantum light source module, through the first output waveguide / the second output waveguide, and finally from the first output optical fiber and the second output optical fiber; detecting the |1,1> term of the output state (|1,1> means that the first output optical fiber detects 1 photon and the second output optical fiber also detects 1 photon, which is a two-photon coincidence count) can achieve 4 times phase sensing; Detecting the |1,3> or |3,1> item of the output state (|3,1> means that the first output fiber detects 3 photons and the second output fiber detects 1 photon, which is a four-photon coincidence count; |1,3> is similar, indicating that the first output fiber detects 1 photon and the second output fiber detects 3 photons, which is also a four-photon coincidence count) can achieve 8-fold phase sensing; detecting the |3,3> item of the output state (|3,3> means that the first output fiber detects 3 photons and the second output fiber detects 3 photons, which is a six-photon coincidence count) can obtain a phase sensing curve of up to 12 times.

[0036] According to some embodiments of the present invention, the material of the photonic quantum chip includes at least one of a third-order nonlinear material and a second-order nonlinear material.

[0037] According to some embodiments of the present invention, the material of the photon chip includes at least one of silicon, silicon nitride, gallium arsenide and lithium niobate, wherein the lithium niobate is the second-order nonlinear material, and the other materials are the third-order nonlinear materials.

[0038] Unless otherwise specified, the interferometers used in the present invention are all 2×2 interferometers, that is, they have two optical path entrances and two optical path exits.

[0039] If not otherwise specified, the interferometer used in the present invention includes a phase adjustment module.

[0040] If not otherwise specified, in the present invention, the phase adjustment module in the interferometer and the phase shifter used include at least one of electro-optical modulation, thermo-optical modulation and optical modulation. The principle is to make electrodes on the interferometer or phase shifter, and change the refractive index of the optical path (also called waveguide) by applying an electric field to modulate the phase of the photon. In actual production, a suitable phase shift adjustment method can be selected according to the object to be measured (temperature, humidity, etc.). As long as the phase shift adjustment method matches the measurement object, the optional phase shift adjustment method has almost no effect on the test results.

[0041] According to an embodiment of the second aspect of the present invention, a method for setting up the photonic quantum chip is provided, and the method for setting up includes performing waveguide processing on the blank.

[0042] Since the setting method adopts all the technical solutions of the optical quantum chip of the above-mentioned embodiment, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiment.

[0043] According to some embodiments of the present invention, the waveguide processing method is at least one of a chemical exchange method, a mechanical cutting method, a chemical mechanical polishing method, an ion beam etching method, and a laser direct writing method. The waveguide processing method is relatively mature in industry. In actual production, a suitable waveguide processing method can be selected based on experience according to the specific structure and material of the photonic quantum chip; and the waveguide processing method has no significant effect on the performance of the obtained photonic quantum chip.

[0044] According to an embodiment of the third aspect of the present invention, there is provided an application of the photon chip in temperature, gas concentration, humidity, electric field and pressure detection.

[0045] Since the application adopts all the technical solutions of the optical quantum chip of the above-mentioned embodiment, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiment.

[0046] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0048] Figure 1 is a schematic diagram of the structure of the photon chip provided in Example 1 of the present invention;

[0049] Figure 2 is the single photon measurement result of turning off and on the adjustable reflection module in the ideal case in Example 2;

[0050] Figure 3 is the two-photon measurement result of turning off and on the adjustable reflection module in the ideal case in Example 3;

[0051] Figure 4 is the four-photon measurement result of turning off and on the adjustable reflection module in Example 4 under ideal conditions;

[0052] Figure 5 is the six-photon measurement result of turning off and on the adjustable reflection module in the ideal case in Example 5;

[0053] Reference numerals:

[0054] Quantum light source module I, phase sensing interference module II, adjustable reflection module III;

[0055] Classical laser 1, input optical fiber 2, grating 3, first Mach-Zehnder interferometer 4, phase shifter 5, waveguide 6, second Mach-Zehnder interferometer 7, third Mach-Zehnder interferometer 8, first multimode interferometer 9, phase shifter to be measured 10, second multimode interferometer 11, bias phase shifter 12, first tail-end connected Mach-Zehnder interferometer 13, fourth Mach-Zehnder interferometer 14, fifth Mach-Zehnder interferometer 15, first output optical fiber 16, second output optical fiber 17, first photon outlet 18, second photon outlet 19, second tail-end connected Mach-Zehnder interferometer 20. DETAILED DESCRIPTION

[0056] The following will be combined with the embodiments to clearly and completely describe the concept of the present invention and the technical effects produced, so as to fully understand the purpose, characteristics and effects of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0057] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0058] In the description of the present invention, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0059] Example 1

[0060] refer to Figure 1 In this example, non-degenerate spontaneous four-wave mixing in silicon-based materials is used as an example to set up a photon chip that can sense up to 12 times the phase, and provide an application for adjusting the phase, specifically:

[0061] The optical quantum chip provided in this example includes a quantum light source module I, a phase sensing interference module II and an adjustable reflection module III which are connected in sequence.

[0062] Quantum light source module I includes:

[0063] An input optical fiber 2, a grating 3 and a first Mach-Zehnder interferometer 4 are connected and arranged;

[0064] A phase shifter 5 and a first intermediate optical path arranged in parallel and connected to the first Mach-Zehnder interferometer 4;

[0065] A fourth Mach-Zehnder interferometer 14 and a fifth Mach-Zehnder interferometer 15 are arranged in parallel; specifically, the fourth Mach-Zehnder interferometer 14 is connected to the phase shifter 5; the fifth Mach-Zehnder interferometer 15 is connected to the first intermediate optical path;

[0066] The waveguide 6 has two entrances connected to the fourth Mach-Zehnder interferometer 14 and the fifth Mach-Zehnder interferometer 15 respectively; the waveguide 6 is a straight waveguide wound into a spiral shape;

[0067] A second Mach-Zehnder interferometer 7 and a third Mach-Zehnder interferometer 8 are arranged in parallel and connected to two outlets of the waveguide 6;

[0068] The quantum light source module I of this example also includes a first output waveguide and a first output optical fiber 16 which are sequentially connected to the fourth Mach-Zehnder interferometer 14; and a second output waveguide and a second output optical fiber 17 which are connected to the fifth Mach-Zehnder interferometer 15.

[0069] In this example, the second Mach-Zehnder interferometer 7 , the third Mach-Zehnder interferometer 8 , the fourth Mach-Zehnder interferometer 14 and the fifth Mach-Zehnder interferometer 15 are unequal-arm Mach-Zehnder interferometers.

[0070] Phase Sensing Interferometry Module II includes:

[0071] The first multimode interferometer 9, the phase shifter 10 to be measured and the second intermediate optical path arranged in parallel with the quantum light source module I, the second multimode interferometer 11, the bias phase shifter 12 and the third intermediate optical path arranged in parallel with the quantum light source module I are sequentially connected.

[0072] in,

[0073] The first multimode interferometer 9 and the second multimode interferometer 11 are 50:50 interferometers.

[0074] Adjustable Reflection Module III includes:

[0075] A first tail end connected to the bias phase shifter 12 is connected to a Mach-Zehnder interferometer 13, and a first photon outlet 18 connected thereto;

[0076] A Mach-Zehnder interferometer 20 connected to the second tail end of the third intermediate optical path, and a second photon outlet 19 connected thereto;

[0077] In this example, the tail-end connected Mach-Zehnder interferometer 13 and the tail-end connected Mach-Zehnder interferometer 20 are specifically 2×2 Mach-Zehnder interferometers, and the two exit ends thereof are connected.

[0078] In this example, the photonic quantum chip is made of silicon, and the other interferometers are all 2×2 interferometers. In the interferometers and phase shifters, the phase shift adjustment method used is at least one of electro-optical modulation, thermo-optical modulation, and optical-optical modulation.

[0079] In this example, the method for setting up the photonic quantum chip is to perform waveguide processing on the blank, and the waveguide processing method is at least one of a chemical exchange method, a mechanical cutting method, a chemical mechanical polishing method, an ion beam etching and laser direct writing.

[0080] In actual use,

[0081] The classical laser 1 is coupled into the grating 3 via the input optical fiber 2, and then is equally divided into two paths by the first Mach-Zehnder interferometer 4 (adjustable), one of which has a phase shifter 5 for adjusting the relative phase of the two paths; the other path passes through the first intermediate optical path. After that, the two paths pass through the fourth Mach-Zehnder interferometer 14 and the fifth Mach-Zehnder interferometer 15 respectively, and then enter a waveguide 6 respectively. The two paths of light generated by the waveguide 6 pass through the second Mach-Zehnder interferometer 7 and the third Mach-Zehnder interferometer 8 connected in parallel respectively. The process pump light is filtered out, and the converted photons then enter the phase sensing interferometer module II, realizing the separation of pump light and converted photons. In the phase sensing interferometer module II, the converted photons first pass through the first multimode interferometer 9, then the upper path passes through the phase shifter 10 to be measured, and the lower path passes through the second intermediate optical path, and then they are collected and split in the second multimode interferometer 11, and the upper path passes through a bias phase shifter 12, and the lower path passes through the third intermediate optical path. The two paths of converted photons enter the adjustable reflection module III respectively into the Mach-Zehnder interferometer 13 connected to the first end and the Mach-Zehnder interferometer 20 connected to the second end.

[0082] When the phases of the first end-connected Mach-Zehnder interferometer 13 and the second end-connected Mach-Zehnder interferometer 20 are both adjusted to Pi / 2 (working state), the converted photons can return to the phase sensing interference module II along the original path, and finally be transferred to the two output waveguides from the fourth Mach-Zehnder interferometer 14 and the fifth Mach-Zehnder interferometer 15 in the quantum light source module I, and finally pass through the first output waveguide and the second output waveguide, and are output from the first output optical fiber 16 and the second output optical fiber 17 for detection. Detecting the |1,1> term of the output state can achieve 4 times phase induction; detecting the |1,3> or |3,1> term of the output state can achieve 8 times phase induction; detecting the |3,3> term of the output state can obtain a maximum 12 times phase induction curve.

[0083] If the Mach-Zehnder interferometer 13 connected to the first tail end and the Mach-Zehnder interferometer 20 connected to the second tail end are not working (the phases are adjusted to 0 or Pi), photons are output from the first photon outlet 18 and the second photon outlet 19, and detecting the |1,1> item of the output state can achieve 2-fold phase induction; detecting the |1,3> or |3,1> item of the output state can achieve 4-fold phase induction; detecting the |3,3> item of the output state can obtain a 6-fold phase induction curve.

[0084] Example 2

[0085] This example provides a specific application of the photonic quantum chip obtained in Example 1:

[0086] The wavelength of the classical laser 1 (pump light) is 1550.92 nm. When the phase shifter 5 is adjusted to Pi, and the Mach-Zehnder interferometer 13 connected to the first tail end and the Mach-Zehnder interferometer 20 connected to the second tail end are not working, the light field intensity at the first photon outlet 18 or the second photon outlet 19 is measured, and a single-phase-induced interference curve can be obtained. When the phase shifter 5 and the bias phase shifter 12 are set to Pi, and the Mach-Zehnder interferometer 13 connected to the first tail end and the Mach-Zehnder interferometer 20 connected to the second tail end are working, the light field intensity at the output of the first output optical fiber 16 or the second output optical fiber 17 is measured, and a double-phase-induced interference curve can be obtained. In this example, the specific results of whether the Mach-Zehnder interferometer 13 connected to the first tail end and the Mach-Zehnder interferometer 20 connected to the second tail end are turned on are as follows. Figure 2 shown.

[0087] Example 3

[0088] This example provides a specific application of the photonic quantum chip obtained in Example 1:

[0089] The wavelength of the classical laser 1 (pump light) is 1550.92 nm, and the signal light and idle light in the photon pair are 1554.94 nm and 1547.72 nm respectively. When the phase shifter 5 is set to Pi, and the Mach-Zehnder interferometer 13 connected to the first tail end and the Mach-Zehnder interferometer 20 connected to the second tail end are not working, the photons at the first photon outlet 18 and the second photon outlet 19 are measured, and the |1,1> term of the output state is detected, and an interference curve with a double phase induction can be obtained. When the phase shifter 5 and the bias phase shifter 12 are set to Pi, and the Mach-Zehnder interferometer 13 connected to the first tail end and the Mach-Zehnder interferometer 20 connected to the second tail end are working, the photons at the first output optical fiber 16 and the second output optical fiber 17 are measured, and the |1,1> term of the output state is detected, and an interference curve with a quadruple phase induction can be obtained. In this example, the specific results of whether the Mach-Zehnder interferometer 13 connected to the first tail end and the Mach-Zehnder interferometer 20 connected to the second tail end are turned on are as follows. Figure 3 shown.

[0090] The difference between this embodiment and embodiment 2 is that this embodiment measures two-photon coincidence counting, while embodiment 2 measures single-photon counting.

[0091] Example 4

[0092] This example provides a specific application of the photonic quantum chip obtained in Example 1:

[0093] The wavelength of the classical laser 1 (pump light) is 1550.92nm, and the signal light and idle light in the photon pair are 1554.94nm and 1547.72nm respectively. When the phase shifter 5 is set to Pi, the Mach-Zehnder interferometer 13 connected to the first tail end and the Mach-Zehnder interferometer 20 connected to the second tail end are not working, the photons at the first photon outlet 18 and the second photon outlet 19 are measured, and the |3,1> term or |1,3> term of the output state is detected, and an interference curve with 4 times phase induction can be obtained. When the phase shifter 5 and the bias phase shifter 12 are set to Pi, the Mach-Zehnder interferometer 13 connected to the first tail end and the Mach-Zehnder interferometer 20 connected to the second tail end are working, the photons at the first output optical fiber 16 and the second output optical fiber 17 are measured, and the |3,1> term or |1,3> term of the output state is detected, and an interference curve with 8 times phase induction can be obtained. In this example, the specific result of whether the first end connected to the Mach-Zehnder interferometer 13 and the second end connected to the Mach-Zehnder interferometer 20 are turned on is as follows: Figure 4 shown.

[0094] The difference between this embodiment and embodiment 2 is that this embodiment measures four-photon coincidence counting, while embodiment 2 measures single-photon counting.

[0095] Example 5

[0096] This example provides a specific application of the photonic quantum chip obtained in Example 1:

[0097] The wavelength of the classical laser 1 (pump light) is 1550.92nm, and the signal light and idle light in the photon pair are 1554.94nm and 1547.72nm respectively. When the phase shifter 5 is set to ArcCos (-3 / 5), the Mach-Zehnder interferometer 13 connected to the first tail end and the Mach-Zehnder interferometer 20 connected to the second tail end are not working, the photons at the first photon outlet 18 and the second photon outlet 19 are measured, and the |3,3> term of the output state is detected, and an interference curve with 6 times phase induction can be obtained. When the phase shifter 5 is set to ArcCos (-3 / 5) and the bias phase shifter 12 is set to Pi, the Mach-Zehnder interferometer 13 connected to the first tail end and the Mach-Zehnder interferometer 20 connected to the second tail end are working, the photons at the first output fiber 16 and the second output fiber 17 are measured, and the |3,3> term of the output state is detected, and an interference curve with 12 times phase induction can be obtained. In this example, the specific result of whether the first end connected to the Mach-Zehnder interferometer 13 and the second end connected to the Mach-Zehnder interferometer 20 are turned on is as follows: Figure 5 shown.

[0098] The difference between this embodiment and embodiment 2 is that this embodiment measures six-photon coincidence counting, while embodiment 2 measures single-photon counting.

[0099] According to the above records, the photon chip provided by the present invention can obtain an interference curve of up to 12 times the phase induction through a reasonable structural setting, with high resolution, accuracy and stability; in addition, the photon chip provided by the present invention has the effects of high integration and high spatial resolution; finally, the present invention can select a suitable phase adjustment method to realize multi-parameter sensing detection such as temperature, gas concentration, humidity, electric field, and pressure.

[0100] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the purpose of the present invention. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

Claims

1. A highly sensitive quantum sensing photon chip, characterized in that: The optical quantum chip comprises a quantum light source module (I), a phase sensing interference module (II) and an adjustable reflection module (III) which are connected in sequence.

2. The photon chip according to claim 1, characterized in that: The quantum light source module (I) comprises: The first Mach-Zehnder interferometer (4); A phase shifter (5), the phase shifter (5) being connected to an optical path outlet of the first Mach-Zehnder interferometer (4); A waveguide (6), wherein the waveguide (6) is connected to the phase shifter (5); A second Mach-Zehnder interferometer (7) and a third Mach-Zehnder interferometer (8) are arranged in parallel and connected to the waveguide (6).

3. The photon chip according to claim 1, characterized in that: The phase sensing interference module (II) comprises a first multimode interferometer (9), a phase shifter to be measured (10), a second multimode interferometer (11) and a bias phase shifter (12) which are sequentially connected to the quantum light source module (I).

4. The photon chip according to claim 1, characterized in that: The adjustable reflection module (III) comprises a first tail end connected to a Mach-Zehnder interferometer (13) and a second tail end connected to a Mach-Zehnder interferometer (20) connected to the phase sensing interference module (II); and a first photon outlet (18) connected to the Mach-Zehnder interferometer (13) connected to the first tail end, and a second photon outlet (19) connected to the Mach-Zehnder interferometer (20) connected to the second tail end.

5. The photon quantum chip according to any one of claims 1 to 4, characterized in that: The quantum light source module (I) further comprises a fourth Mach-Zehnder interferometer (14) and a fifth Mach-Zehnder interferometer (15) which are arranged in parallel between the first Mach-Zehnder interferometer (4) and the waveguide (6).

6. The photon chip according to claim 5, characterized in that: The optical quantum chip also includes a first output optical fiber (16) connected to the fourth Mach-Zehnder interferometer (14).

7. The photon chip according to claim 5, characterized in that: The optical quantum chip also includes a second output optical fiber (17) connected to the fifth Mach-Zehnder interferometer (15).

8. The photon quantum chip according to any one of claims 1 to 4, characterized in that: The material of the photonic quantum chip includes at least one of a third-order nonlinear material and a second-order nonlinear material; preferably, the material of the photonic quantum chip includes at least one of silicon, silicon nitride, gallium arsenide and lithium niobate.

9. A method for setting up a photon chip as claimed in any one of claims 1 to 8, characterized in that: The arrangement method includes performing waveguide processing on the blank.

10. Application of the photon chip as claimed in any one of claims 1 to 8 in temperature, gas concentration, humidity, electric field and pressure detection.

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