An application for 87 All-fiber laser optical system for Rb cold atom interferometer

Abstract

The application provides a kind of applied to 87 The all-fiber laser optical path system of Rb cold atom interferometer includes a plurality of fiber amplifiers, a plurality of fiber acousto-optic modulators, a plurality of fiber beam combiners, a plurality of fiber beam splitters, a fiber frequency doubling waveguide and a beat frequency phase-locked servo module. Through the all-fiber laser optical path system, different frequency lasers required by the Rb cold atom interferometer can be generated 87 The all-fiber laser optical path system not only can replace the complex laboratory laser optical path system of the cold atom interferometer, but also has smaller volume, stronger environmental adaptability, higher reliability and simpler process, and can meet the requirements of various functional lasers of the Rb cold atom interferometer 87 Therefore, the all-fiber laser optical path system can be used as an important component of the miniaturization, integration, modularization and engineering of the laser optical path of the Rb cold atom interferometer 87 Therefore, the all-fiber laser optical path system can be used as an important component of the miniaturization, integration, modularization and engineering of the laser optical path of the Rb cold atom interferometer

Description

Technical Field

[0001] This invention relates to the field of cold atom interferometry, and more specifically, to a method applied to... 87 The all-fiber laser optical path system of Rb cold atom interferometer. Background Technology

[0002] Quantum sensors based on cold atom interferometry are a new type of sensor that uses matter-wave interference as a medium. Due to their extremely high theoretical measurement accuracy and broad application prospects in gravity measurement and inertial sensing, they are currently recognized worldwide as important candidates for the next generation of high-precision inertial sensors. Atomic interferometry has been widely applied in precision measurement, and various quantum sensors based on cold atom interferometry, such as cold atom interferometric absolute gravimeters, cold atom interferometric gravity gradiometers, and cold atom interferometric gyroscopes, have experienced rapid development.

[0003] After nearly 30 years of development, significant progress has been made in various quantum sensors based on cold atom interferometry, such as cold atom interferometric absolute gravimeters, cold atom interferometric gravity gradiometers, and cold atom interferometric gyroscopes. In particular, the cold atom interferometric absolute gravimeter has not only achieved the measurement accuracy and performance level of the current mainstream commercial laser interferometric absolute gravimeter FG5, but has also begun to move out of the laboratory and towards commercialization. Quantum sensors based on cold atom interferometry are gradually moving out of the laboratory and developing towards miniaturization, integration, modularization, and engineering. Summary of the Invention

[0004] This invention addresses the needs of existing technologies by providing an application for... 87 The all-fiber laser optical path system of the Rb cold atom interferometer is small in size, highly adaptable to the environment, and highly reliable.

[0005] This invention provides an application for 87 The all-fiber laser optical path system of the Rb cold atom interferometer includes multiple fiber amplifiers, multiple fiber acousto-optic modulators, multiple fiber combiners, multiple fiber splitters, fiber frequency doubling waveguides, and beat frequency phase-locked servo modules.

[0006] The first fiber laser seed source is split into two fundamental frequency beams after passing through the first fiber amplifier and the first fiber beam splitter. The first fundamental frequency beam is injected into the first fiber frequency doubling waveguide to obtain the first frequency-doubled laser. The first frequency-doubled laser passes through the first fiber acousto-optic modulator to obtain the laser required by the cold atom interferometer. The second fundamental frequency beam is split into two frequency-shifted lasers after passing through the second fiber acousto-optic modulator and the second fiber beam splitter. The first frequency-shifted laser passes through the fiber optical switch and is injected into the first fiber beam combiner, and the second frequency-shifted laser is injected into the second fiber beam combiner.

[0007] The second fiber laser seed source is split into two fundamental frequency beams by the third fiber beam splitter. The third fundamental frequency beam is input into the first fiber beam combiner and combined with the first frequency-shifted laser beam. After passing through the second fiber amplifier and the second fiber frequency-doubled waveguide, the second frequency-doubled laser beam is obtained. The second frequency-doubled laser beam is then passed through the third fiber acousto-optic modulator to obtain the laser beam required by the cold atom interferometer. The fourth fundamental frequency beam is injected into the second fiber beam combiner and combined with the second frequency-shifted laser beam to obtain the beat frequency beam, which is input into the photodetector to obtain the beat frequency signal required by the beat frequency phase-locked servo module.

[0008] This invention provides an application for 87 The all-fiber laser optical path system of the Rb cold atom interferometer can generate different lasers required by the cold atom interferometer. The all-fiber laser optical path system can not only replace the complex laboratory laser optical path system of the cold atom interferometer, but also has a smaller size, stronger environmental adaptability, higher reliability, and simpler process. It can meet the laser requirements of various functions of the cold atom interferometer. Therefore, it can serve as an important technical path for the miniaturization, integration, modularization, and engineering of the laser optical path of the cold atom interferometer. Attached Figure Description

[0009] Figure 1 The present invention provides an application for 87 A schematic diagram of the all-fiber laser optical path system of the Rb cold atom interferometer. Detailed Implementation

[0010] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. In addition, the technical features of the various embodiments or individual embodiments provided by the present invention can be arbitrarily combined with each other to form feasible technical solutions. Such combinations are not constrained by the order of steps and / or structural composition patterns, but must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0011] Figure 1 The present invention provides an application for 87 The all-fiber laser optical path system of the Rb cold atom interferometer, such as Figure 1As shown, the all-fiber laser optical path system includes multiple fiber amplifiers, multiple fiber acousto-optic modulators, multiple fiber combiners, multiple fiber splitters, fiber frequency doubling waveguides, and beat frequency phase-locked servo modules.

[0012] The working process of the all-fiber laser optical path system is as follows: The first fiber laser seed source is split into two fundamental frequency beams after passing through the first fiber amplifier and the first fiber beam splitter. The first fundamental frequency beam is injected into the first fiber frequency doubling waveguide to obtain the first frequency-doubled laser. The first frequency-doubled laser passes through the first fiber acousto-optic modulator to obtain the laser required by the cold atom interferometer. The second fundamental frequency beam is split into two frequency-shifted laser beams after passing through the second fiber acousto-optic modulator and the second fiber beam splitter. The first frequency-shifted laser passes through the fiber-optic switch and is injected into the first fiber combiner, and the second frequency-shifted laser is injected into the second fiber combiner.

[0013] The second fiber laser seed source is split into two fundamental frequency beams by a third fiber beam splitter. The third fundamental frequency beam is input into a first fiber combiner, combined with the first frequency-shifted laser beam, and then passes through a second fiber amplifier and a second fiber frequency-doubled waveguide to obtain a second frequency-doubled laser beam. The second frequency-doubled laser beam passes through a third fiber acousto-optic modulator to obtain the laser beam required by the cold atom interferometer. A fourth fundamental frequency beam is injected into the second fiber combiner, combined with the second frequency-shifted laser beam to obtain a beat frequency beam, which is input into a photodetector to obtain the beat frequency signal required by the beat frequency phase-locked servo module.

[0014] The all-fiber laser optical path system further includes a fourth fiber beam splitter and a fourth fiber acousto-optic modulator. The first frequency-doubled laser is split into two first frequency-doubled laser beams by the fourth fiber beam splitter. One of the first frequency-doubled laser beams is passed through the first fiber acousto-optic modulator to obtain the cooling light / blowing light / probe light of the cold atom interferometer. The other first frequency-doubled laser beam is passed through the fourth fiber acousto-optic modulator to obtain the frequency-stabilized laser of the cold atom interferometer.

[0015] Specifically, the working process of the all-fiber laser optical path system provided by this invention includes the following steps:

[0016] Step S1: Inject the seed source (Seed1) of the first fiber laser into the first fiber amplifier to obtain approximately 5W of 1560nm fundamental frequency light;

[0017] Step S2: Based on the approximately 5W 1560nm fundamental frequency light from step S1, the fiber optic pigtail is fused with the first fiber optic beam splitter to obtain two beams of 1560nm fundamental frequency light with 10% / 90% of each other.

[0018] In step S3, 90% of the 1560nm fundamental frequency light from step S2 is fused to the first fiber frequency doubling waveguide via a pigtail, and approximately 1W of 780nm frequency-doubled laser is obtained through frequency doubling technology. 10% of the 1560nm fundamental frequency light is fused to the second fiber acousto-optic modulator via a pigtail, and a 1560nm fundamental frequency light with a frequency shift of -1.2 GHz is obtained.

[0019] Step S4: The 780nm frequency-doubled laser from step S3 is passed through a pigtail and a fourth fiber beam splitter to obtain two 780nm laser beams with 10% and 90% of their original values.

[0020] Step S5: 10% of the 780nm laser from step S4 is fused to the fourth fiber acousto-optic modulator via a pigtail to obtain the frequency-stabilized laser of the MTS laser frequency stabilization module of the 87Rb cold atom interferometer; 90% of the 780nm laser is fused to the first fiber acousto-optic modulator via a pigtail to obtain the cooling light / blowing light / probe light of the 87Rb cold atom interferometer.

[0021] Step S6: The 1560nm fundamental frequency light with a frequency shift of -1.2GHz from step 3 is fused to the second fiber optic beam splitter via a pigtail to obtain two beams of 1560nm fundamental frequency light with a frequency shift of -1.2GHz and a ratio of 10% / 90%.

[0022] Step S7: 90% of the 1560nm fundamental frequency light shifted by 1.2GHz from step 6 is fused to a fiber optic switch via a pigtail to obtain a 1560nm fundamental frequency light shifted by 1.2GHz that can be switched and controlled.

[0023] Step S8: The second fiber laser seed source (Seed2) is fused to the third fiber beam splitter via a pigtail to obtain two beams of 1560nm fundamental frequency light with 10% / 90% ratio.

[0024] Step S9: 10% of the frequency-shifted -1.2GHz 1560nm fundamental frequency light from step 6 and 10% of the 1560nm fundamental frequency light from step 8 are fused to the two input ends of the second fiber combiner via pigtails, and the beat frequency light output from the second fiber combiner is injected into the fast photodetector to obtain the beat frequency signal required by the beat frequency phase-locked servo module.

[0025] In step S10, 90% of the 1560nm fundamental frequency light from step 9 and the 1560nm fundamental frequency light with a frequency shift of -1.2GHz that can be switched and controlled from step 7 are fused to the two input ends of the first fiber optic combiner via pigtails, and the output light of the first fiber optic combiner is injected into the second fiber optic amplifier to obtain approximately 5W of 1560nm fundamental frequency light.

[0026] Step S11: The approximately 5W 1560nm fundamental frequency light from step 10 is fused to the second fiber frequency doubling waveguide via a pigtail. Through frequency doubling technology, approximately 1W 780nm frequency doubling laser is obtained.

[0027] Step S12: The 780nm light from step 11 is fused to the third fiber acousto-optic modulator via a pigtail to obtain... 87 Pump backlight and Raman light of Rb cold atom interferometer.

[0028] In one possible embodiment of the present invention, the center wavelength of the first fiber laser seed source and the second fiber laser seed source is 1560nm, the laser linewidth is 2kHz, the output power is 40mW, the polarization degree is better than 20dB, the fast frequency tuning bandwidth is 5kHz, and the fast frequency tuning range is 3GHz.

[0029] The first and second fiber amplifiers have a center operating wavelength of 1560nm, an incident seed power of 1mW, a maximum output power of 5W, an operating mode of continuous light, and an output relative intensity noise of <1%.

[0030] The first and second fiber frequency-doubled waveguides have an input light wavelength of 1560nm, a frequency-doubled light wavelength of 780nm, an input power of 5W, a maximum output power of 2W, and a temperature tuning range of 20-70℃.

[0031] The first fiber splitter is a 1560nm high-power fiber splitter with a power impairment threshold of 5W; the second and third fiber splitters are 1560nm low-power fiber splitters with a power impairment threshold of 500mW; and the fourth fiber splitter is a 780nm high-power fiber splitter with a power impairment threshold of 2W.

[0032] The first and second fiber combiners are 1560nm low-power fiber combiners with a power impairment threshold of 500mW.

[0033] The first fiber optic acousto-optic modulator is a 780nm frequency-converting fiber optic acousto-optic frequency shifter with a frequency shift range of 100 to 250 MHz; the second fiber optic acousto-optic modulator is a 1550nm fixed-frequency fiber optic acousto-optic frequency shifter with a frequency shift range of -1200 MHz; the third fiber optic acousto-optic modulator is a 780nm fixed-frequency fiber optic acousto-optic frequency shifter with a frequency shift range of -100 MHz; and the fourth fiber optic acousto-optic modulator is a 780nm fixed-frequency fiber optic acousto-optic frequency shifter with a frequency shift range of 200 MHz.

[0034] The fiber optic switch is a silicon-based high-speed optical switch with a switching speed of approximately 0.3 µS; the photodetector is a broadband InGaAs photodetector with a bandwidth of 10 GHz.

[0035] The all-fiber laser optical path system for cold atom interferometers provided in this invention has the following beneficial effects:

[0036] (1) Different lasers required by cold atom interferometers can be generated through the all-fiber laser optical path system. The all-fiber laser optical path system can not only replace the complex laboratory laser optical path system of cold atom interferometers, but also has a smaller size, stronger environmental adaptability, higher reliability and simpler process. It can meet the needs of various functional lasers of cold atom interferometers. Therefore, it can be used as an important technical path for the miniaturization, integration, modularization and engineering of the laser optical path of cold atom interferometers.

[0037] (2) The provided all-fiber laser optical path system is simple to implement, smaller in size, more adaptable to the environment, and more reliable. It is of great significance to promote the development of cold atom interferometry technology and advance the application of cold atom interferometers.

[0038] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0039] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0040] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. An application for 87 A fully fiberized laser optical system for a Rb cold atom interferometer, characterized by, The system comprises a plurality of fiber amplifiers, a plurality of fiber acousto-optic modulators, a plurality of fiber combiners, a plurality of fiber splitters, fiber frequency-doubling waveguides, and a beat frequency phase-locked servo module. The first fiber laser seed source is split into two beams of fundamental light after passing through the first fiber amplifier and the first fiber splitter, and the first beam of fundamental light is injected into the first fiber frequency-doubling waveguide to obtain the first frequency-doubled laser, which is then passed through the first fiber acousto-optic modulator to obtain the laser required by the cold atom interferometer; the second beam of fundamental light is split into two beams of frequency-shifted laser after passing through the second fiber acousto-optic modulator and the second fiber splitter, and the first beam of frequency-shifted laser is injected into the first fiber combiner through the fiber optical switch, and the second beam of frequency-shifted laser is injected into the second fiber combiner. The second fiber laser seed source is split into two beams of fundamental light after passing through the third fiber splitter, and the third beam of fundamental light is input into the first fiber combiner, combined with the first beam of frequency-shifted laser, and then passed through the second fiber amplifier and the second fiber frequency-doubling waveguide to obtain the second frequency-doubled laser, which is then passed through the third fiber acousto-optic modulator to obtain the laser required by the cold atom interferometer; the fourth beam of fundamental light is injected into the second fiber combiner, combined with the second beam of frequency-shifted laser to obtain the beat frequency light input into the photodetector, and the beat frequency signal required by the beat frequency phase-locked servo module is obtained. The system further comprises a fourth fiber splitter and a fourth fiber acousto-optic modulator. The first frequency-doubled laser is split into two beams of first frequency-doubled laser through the fourth fiber splitter, one of which is passed through the first fiber acousto-optic modulator to obtain the cooling light / blow-off light / detection light of the cold atom interferometer, and the other of which is passed through the fourth fiber acousto-optic modulator to obtain the frequency-stabilized laser of the cold atom interferometer.

2. The all-fiber laser optical system according to claim 1, characterized in that, The first fiber splitter is used to split the fundamental light into a first beam of fundamental light with a proportion of 80-90% and a second beam of fundamental light with a proportion of 10-20%. The second fiber splitter is used to split the frequency-shifted laser into a first beam of frequency-shifted laser with a proportion of 80-90% and a second beam of frequency-shifted laser with a proportion of 10-20%. The third fiber splitter is used to split the fundamental light of the second fiber laser seed source into a third beam of fundamental light with a proportion of 80-90% and a fourth beam of fundamental light with a proportion of 10-20%.

3. The all-fiber laser optical system according to claim 1, wherein, The center wavelength of the first fiber laser seed source and the second fiber laser seed source is 1560 nm, the laser linewidth is 2 kHz, the output power is 40 mW, the degree of polarization is better than 20 dB, the fast frequency tuning bandwidth is 5 kHz, and the fast frequency tuning range is 3 GHz.

4. The all-fiber laser optical system of claim 1, wherein, The center working wavelength of the first fiber amplifier and the second fiber amplifier is 1560 nm, the incident seed power is 1 mW, the maximum output power is 5 W, the working mode is continuous light, and the output relative intensity noise is less than 1%.

5. The all-fiber laser optical system of claim 1, wherein, The input light wavelength of the first fiber frequency-doubling waveguide and the second fiber frequency-doubling waveguide is 1560 nm, the frequency-doubled light wavelength is 780 nm, the input power is 5 W, the maximum output power is 2 W, and the temperature tuning range is 20-70℃.

6. The all-fiber laser optical system of claim 1, wherein, The first optical fiber beam splitter is a 1560nm high-power optical fiber beam splitter device, the power damage threshold is 5W, the second optical fiber beam splitter and the third optical fiber beam splitter are 1560nm low-power optical fiber beam splitter devices, the power damage threshold is 500mW, and the fourth optical fiber beam splitter is a 780nm high-power optical fiber beam splitter device, the power damage threshold is 2W.

7. The all-fiber laser optical system of claim 1, wherein, The first optical fiber combiner and the second optical fiber combiner are 1560nm low-power optical fiber combiners, and the power damage threshold is 500mW.

8. The all-fiber laser optical system of claim 1, wherein, The first optical fiber acousto-optic modulator is a 780nm frequency conversion optical fiber acousto-optic frequency shifter, and the frequency shift frequency is 100-250MHz; the second optical fiber acousto-optic modulator is a 1550nm fixed-frequency optical fiber acousto-optic frequency shifter, and the frequency shift frequency range is-1200MHz; the third optical fiber acousto-optic modulator is a 780nm fixed-frequency optical fiber acousto-optic frequency shifter, and the frequency shift frequency is-100MHz; and the fourth optical fiber acousto-optic modulator is a 780nm fixed-frequency optical fiber acousto-optic frequency shifter, and the frequency shift frequency is 200MHz.

9. The all-fiber laser optical system of claim 1, wherein, The optical fiber optical switch is a silicon-based high-speed optical switch, and the switching speed is about 0.3uS; and the photoelectric detector is a broadband InGaAs photoelectric detector, and the bandwidth is 10GHz.

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