CN112362039A

CN112362039A - Separated Raman laser type atomic interference gyro device and debugging method

Info

Publication number: CN112362039A
Application number: CN202011182802.0A
Authority: CN
Inventors: 姚战伟; 陈红辉; 鲁思滨; 李润兵; 余庚华; 罗军; 王谨; 詹明生
Original assignee: Institute of Precision Measurement Science and Technology Innovation of CAS
Current assignee: Institute of Precision Measurement Science and Technology Innovation of CAS
Priority date: 2020-10-29
Filing date: 2020-10-29
Publication date: 2021-02-12
Anticipated expiration: 2040-10-29
Also published as: CN112362039B

Abstract

The invention discloses a separated Raman laser type atomic interference gyro device which comprises an atomic interference physical system, an alkali metal atom source, laser cooling lasers, three Raman lasers, three reflectors matched with the lasers, detection lasers and a photoelectric detector. Meanwhile, the invention also discloses a method for debugging the separated Raman laser type atomic interference gyroscope, which can improve the phase measurement precision and simplify the debugging process of the large-area atomic interferometer. The method can be used in the technical field of atomic inertial sensing, and the measurement sensitivity of the atomic interference gyroscope is improved.

Description

Separated Raman laser type atomic interference gyro device and debugging method

Technical Field

The invention relates to the technical field of atomic inertia measurement, in particular to a debugging method of a separated Raman laser type atomic interference gyroscope and a separated Raman laser type atomic interference gyroscope device.

Background

The high-precision atomic interference gyroscope can be used in the fields of inertial navigation, geophysical measurement and the like. Like an optical gyroscope, the measurement accuracy of a cold atom interferometric gyroscope is proportional to the area of interference. Compared with an optical gyroscope, the atomic substance has shorter wavelength and lower atomic speed, and the atomic interference gyroscope under the same loop area has higher rotation sensitivity. To improve the accuracy of the atomic interference gyroscope, the atomic interference gyroscope needs to increase the loop area by using a separate raman laser. Limited by the finite coherence length of the atoms, the raman laser direction in a split raman laser type atomic interferometer requires high precision adjustment to ensure the coherence of the atoms during the measurement.

To achieve high Precision angle adjustment of the separated raman laser, t.l. gusstavson et al (Precision Rotation Sensing Using Atom interference, phd article, university of stanford, 2000) adjusts the laser angle Using a method of measuring the transition frequency. Tackmann et al (New Journal of Physics, volume 14, p.015002, 2012) adjust the parallelism of the separated raman laser light using a method that maximizes the contrast of the symmetric lammlike-bird interferometer. Dutta et al (Physical Review Letters, volume 116, page 183003, 2016) then implemented raman laser angle modulation for a four-pulse configuration interferometer using a method of measuring transition frequency and maximizing raman-fringe-bird interferometer contrast. In contrast, the angular accuracy in the method of measuring the transition frequency is directly proportional to the atomic velocity, and for atoms with lower velocities, the angular resolution of the method cannot achieve the accuracy required for atomic interference. Meanwhile, the measurement accuracy of the contrast maximization method is related to the size of the Raman light spot, and when the length of the interference arm is large relative to the size of the light spot, the measurement accuracy of the method is not enough to realize the accurate angle adjustment of the separated Raman laser.

Disclosure of Invention

The invention aims to provide a debugging method of a separated Raman laser type atomic interference gyroscope and a separated Raman laser type atomic interference gyroscope device aiming at the problem that the measurement precision of a Raman laser angle in the existing separated Raman laser type atomic interference gyroscope is not enough. The invention measures the angle of the Raman laser by using the interference phase of the symmetrical Lamzier-Berd interferometer, and can improve the measurement precision of the angle of the Raman laser. Compared with a transition frequency measurement method and a contrast measurement method, the phase measurement can realize angle measurement with higher precision. The method can improve the interference loop area of the atomic interference gyroscope, and can be applied to the fields of atomic inertia sensing technology and the like.

The above object of the present invention is achieved by the following technical solutions:

the separated Raman laser type atomic interference gyro device comprises an atomic interference physical system, wherein one end of the atomic interference physical system is a projecting end, the other end of the atomic interference physical system is a light emitting end, first Raman laser, second Raman laser and third Raman laser are sequentially distributed on one side of the atomic interference physical system from the projecting end to the light emitting end, and a first reflecting mirror, a second reflecting mirror and a third reflecting mirror are sequentially distributed on the other side of the atomic interference physical system from the projecting end to the light emitting end;

the cooling laser is positioned at the projecting end of the atomic interference physical system, the photoelectric detector is positioned at the light emitting end of the atomic interference physical system, and the detection laser is positioned at the light emitting end of the atomic interference physical system.

The debugging method of the separated Raman laser type atomic interference gyroscope comprises the following steps:

step 1, an alkali metal atom source moves along a preset atom projection track under the action of cooling laser;

step 2, defining i as the number of atom throwing, j as the serial numbers of different interval time, and setting the initial values of i and j to be 1;

and 3, carrying out ith atom projection, and when the alkali metal atoms of the alkali metal atom source pass through the positions of the first pair of Raman lasers, sequentially providing three pairs of laser pulses by the first pair of Raman lasers, wherein the three pairs of laser pulsesTime interval t_j＝t₀+(j-1)δt₀，t₀For an initial time interval, δ t₀The second and third pairs of Raman lasers are turned off for time interval increments at different chirp rates alpha_i＝(i-1)×δα+α₀Scanning Raman laser frequency difference delta omega, wherein delta alpha is chirp rate increment and alpha₀For the initial chirp rate, when an alkali metal atom of the alkali metal atom source reaches the photodetector, an output signal P of the photodetector is recorded_jiFitting the interference fringes to obtain the time interval t_jUnder the condition of phase phi (alpha)_jLinear function relationship phi (alpha) with chirp rate alpha_j＝A_j+B_jX α; wherein A is_jAnd B_jAre all fitting coefficients;

step 4, increasing i by 1, and repeating the step 3 until the current time interval t is traversed_jAll atoms below cast;

step 5, increasing j by 1, setting i as 1, and returning to the step 3 until all the interval time is traversed;

step 6, calculating AG_q＝(A_(q-1)-A_q)/(B_q-B_(q-1)) Is expressed as α_gQ is greater than or equal to 2 and less than or equal to the total number of interval times;

step 7, performing the nth second interference time TS_nSetting, TS_n＝TS₀+ (n-1). times.delta.TS, wherein TS₀Setting the initial second interference time, n is the number of times set by the second interference time, the initial value of n is 1, delta TS is the second interference time increment, and defining that an X axis passes through the center of the first reflector, the positive direction of the X axis is parallel to the projection direction of the alkali atom casting direction on the horizontal plane, a Y axis passes through the center of the first reflector and is positioned on the horizontal plane and is vertical to the X axis, a Z axis is vertical to the horizontal plane, r is the deflection number of times of the Y axis, and the initial value of r is 1;

from the initial state of the first Raman reflector, the first reflector is deflected for the r times by taking the Y axis as a rotating shaft, the deflection directions of all times are the same, the deflection angle of all times is delta theta Y, and r is the deflection times of the Y axis; the second Raman laser is turned on, the second reflector is kept still, and the third Raman laser is turned off;

step 8, the frequency of the first Raman laser and the second Raman laser is in chirp rate alpha_gThe scanning is carried out by scanning the object,

the alkali metal atom source moves along a preset atom track under the action of cooling laser, the time when the alkali metal atom moves to the first Raman laser optical axis is recorded as T ', and the time when the alkali metal atom source moves to the second Raman laser optical axis is recorded as T';

at T' -TS_nAt the moment/2, emitting a first Raman laser pulse to split the beam of the alkali metal atom source, wherein the alkali metal atom source in the first ground state in the split alkali metal atom source continues to move along the first path, and the alkali metal atom in the second ground state in the split alkali metal atom continues to move along the second path;

at T' + TS_nAt the time point of/2, emitting a first Raman laser pulse to make alkali metal atoms in a first ground state of a first path transition to a second ground state of the first path,

at T' -TS_nAt time/2, the initial phase difference phi is transmitted₀The second Raman laser pulse of the first path transits the alkali metal atoms of the first ground state of the first path to the second ground state of the second path;

step 9, at T "+ TS_nAt time/2, the phase difference phi (r, TS) of the second Raman laser is adjusted_nM) is phi₀+m×δφ，φ₀For initial phase difference, the initial value of the cycle parameter m is 1, delta phi is phase difference increment, a second Raman laser pulse is emitted, and a first ground state |321 | of a second path is subjected to>And a first path second ground state |312>Combining the beams, opening the detection laser and the photoelectric detector, and recording the output signals P (r, TS) of the photoelectric detector_n，m)；

Step 10, increasing m by 1, repeating the steps 7-9 until all m are traversed, and obtaining the same Y-axis deflection times r and the same interference time TS_nUnder the condition of (d), the output signals P (r, TS) corresponding to different m_n，m)；

Step 11, output signals P (r, TS) of the photoelectric detector obtained in the step 7-10_nM) and corresponding secondPhase difference phi (r, TS) of Raman laser_nM) obtaining the output signal P (r, TS) of the photodetector (103) by fitting_nM) is 0, and the phase difference phi (r, TS) of the second Raman laser_n)；

Step 12, increasing the Y-axis deflection times r by 1, repeating the steps 7-11 until all the Y-axis deflection times are traversed, and obtaining the phase difference phi (r, TS) for the r multiplied by delta theta Y sum_n) Fitting is carried out to obtain a linear function phi (r, TS)_n)＝C_n+D_nXr × δ θ Y, where n is the number of times the second interference time is set;

step 13, increasing n by 1, and repeating the steps 7-12 until n is traversed;

step 14, recording N as a second interference time TS_nThe set total number of times, calculate theta_k＝(C_(k+1)-C_k)/(D_k-D_(k+1)) K is within {1 to (N-1) }, theta_kThe average value of (D) is recorded as the Y-axis deflection angle theta_12y；

Step 15, from the initial state of the first mirror, deflecting the first mirror by a Y-axis deflection angle theta in the deflection direction in step 7 with the Y-axis as the rotation axis_12yThe first reflector is in the final state of Y-axis deflection adjustment,

adjusting a final state through Y-axis deflection of the first reflecting mirror, deflecting the first reflecting mirror for the w-th time by taking an X-axis as a rotating shaft, wherein the direction of each deflection is the same, the angle of each deflection is delta theta X, w is the X-axis deflection frequency, the second Raman laser is opened, the second reflecting mirror is kept still, and the third Raman laser is closed;

selecting the TS set for the last time in the step 8_nRepeat step 8 at T "+ TS_nAt the time point/2, the phase difference phi (w, TS) of the second Raman laser is adjusted_nM1) is phi₀+ m1 × δ Φ, the initial value of the cyclic parameter m1 being 1, emitting a second raman laser pulse, combining alkali metal atoms of the first ground state of the second path and the second ground state of the first path, turning on the detection laser and the photodetector, and recording the output signal P (w, TS) of the photodetector_n，m1)；

Step 16, m1 is increased by 1, and step 15 is repeated until all steps are traversedm1, obtaining the same X-axis deflection times w and interference time TS_nUnder the condition (2), the output signals P (w, TS) corresponding to different m1_n，m1)；

Step 17, increasing the X-axis deflection times w by 1, repeating steps 15 to 16 until all the X-axis deflection times w are traversed, and performing sine fitting to obtain the contrast C corresponding to different deflection angles w × δ θ X (w is 1, 2, 3, 4, 5)_wTo C_wPerforming Gaussian fitting with the function of the angle w multiplied by delta theta X to obtain the angle corresponding to the central value of the Gaussian function, and recording the angle as the X-axis deflection angle theta_12x；

The final state of Y-axis deflection adjustment from the first mirror is obtained by deflecting the first mirror by θ in the deflection direction in step 15 with the X-axis as the rotation axis_12xThe first mirror is in the final state of final deflection adjustment.

Compared with the prior art, the invention has the following beneficial effects:

the invention provides a method for measuring an angle by using an interference phase, which can realize high-precision measurement and debugging of a Raman laser angle in a long-arm interferometer, can be applied to the technical field of high-precision atomic inertia sensing and can improve the measurement precision of an atomic interference gyroscope.

Drawings

FIG. 1 is a separated Raman laser type atomic interference gyroscope device;

FIG. 2 is a schematic diagram of Raman laser driven atomic transition;

FIG. 3 is a timing diagram for debugging a separated Raman laser type atomic interferometer;

FIG. 4 is a diagram of a debugging method of the present invention;

in the figure: 100: atomic interference physical system, 101: cooling laser, 102: detection laser, 103: photodetector, 104: source of alkali metal atoms, 105: atom projection trajectory, 201: first raman laser, 202: second raman laser, 203: third raman laser, 204: first raman reflected laser, 205: second raman reflected laser, 206: third raman reflected laser, 207: first mirror, 208: second mirror, 209: a third mirror.

I301I a first ground state, I302I a second ground state, I304I an excited state, and I303I a virtual energy level; 401: a first laser frequency, 402: a second laser frequency. 311> a first path first ground state; 312> first path second ground state; 322> second path second ground state; 321> second path first ground state.

Detailed Description

The present invention will be described in further detail with reference to examples for the purpose of facilitating understanding and practice of the invention by those of ordinary skill in the art, and it is to be understood that the present invention has been described in the illustrative embodiments and is not to be construed as limited thereto.

In an embodiment, as shown in fig. 1, the separated raman laser type atomic interference gyro device includes an atomic interference physical system 100, where one end of the atomic interference physical system 100 is a projecting end, and the other end is a light emitting end, a first raman laser 201, a second raman laser 202, and a third raman laser 203 are sequentially distributed on one side of the atomic interference physical system 100 from the projecting end to the light emitting end, and a first reflector 207, a second reflector 208, and a third reflector 209 are sequentially distributed on the other side of the atomic interference physical system 100 from the projecting end to the light emitting end;

the cooling laser 101 is located at the projecting end of the atomic interference physical system 100, the photodetector 103 is located at the light emitting end of the atomic interference physical system 100, and the detection laser 102 is located at the light emitting end of the atomic interference physical system 100.

The separated Raman laser type atomic interference gyro device comprises an atomic interference physical system 100, an alkali metal atom source 104, an atom projection track 105, a cooling laser 101, three Raman lasers (202, 202 and 203) and three reflectors (207, 208 and 209) matched with the three Raman lasers, a detection laser 102 and a photoelectric detector 103. The atomic interference physics system 100 implements the vacuum environment required for atomic interference through vacuum techniques. The alkali metal atom source 104 achieves the low temperature atoms required for atomic interference by laser cooling techniques. The alkali metal atoms are projected by the laser at a fixed initial velocity along a predetermined atom projection trajectory 105. Three Raman laser beams (201, 202, 203) form three pairs of Raman laser beams (201 and 204, 202 and 205, 203 and 203) propagating in the front and back directions through three reflecting mirrors (207, 208, 209)206). In the atom projection process, the alkali metal atom source 104 is sequentially acted on by three pairs of Raman lasers (201 and 204, 202 and 205, 203 and 206), as shown in FIG. 2, and the alkali metal atom source 104 can be in a first ground state |301>And a second ground state |302>The laser beam and the laser beam are in reciprocating transition to obtain momentum, so that atomic beam splitting is realized, and the frequency difference delta omega of the Raman laser is equal to omega₁-ω₂Varying at a linear chirp rate to match the gravity-induced doppler shift. When the alkali metal atom source 104 moves to the position of the detection light 102, the alkali metal atom source 104 and the photoelectric detector 103 are turned on, and the atom interference signal is recorded. The vacuum technique and the laser cooling technique are general techniques, and the present invention is not described in detail.

step 1, an alkali metal atom source 104 moves along a preset atom track 105 under the action of a cooling laser 101. One end of the atomic interference physical system 100 is a projecting end, the other end of the atomic interference physical system 100 is a light-emitting end, the first raman laser 201, the second raman laser 202 and the third raman laser 203 are sequentially distributed from the projecting end to the light-emitting end outside the atomic interference physical system 100, the first raman laser 201, the second raman laser 202 and the third raman laser 203 are adjusted to be initially vertical to a horizontal plane, then the first reflector 207 is adjusted to enable the first reverse raman laser 204 to be parallel to the first raman laser 201, and the first raman laser 201 and the first reverse raman laser 204 form a first pair of raman lasers; adjusting the second mirror 208 such that the first inverse raman laser 205 is parallel to the first raman laser 202, the first raman laser 202 and the first inverse raman laser 205 forming a second pair of raman lasers; adjusting the third mirror 209 to make the third reverse raman laser 206 parallel to the third raman laser 203, where the third raman laser 203 and the third reverse raman laser 206 form a third pair of raman lasers;

as shown in fig. 1, the right end of the atomic interference physical system 100 is used as a light emitting end, the alkali metal atom source 104 is projected from the left end to the right end in the atomic interference physical system 100, the cooling laser 101 is located at the left end of the atomic interference physical system 100, the photodetector 103 is located at the right end of the atomic interference physical system 100, the detection laser 102 is located at the right end of the atomic interference physical system 100, and the first pair of raman lasers to the third pair of raman lasers are sequentially distributed along the projection end to the light emitting end of the atomic interference physical system 100;

step 2, defining i as the number of times of atom casting, j as the sequence numbers of different interval time, and the initial values of i and j are both 1, wherein i belongs to {1, 2, 3, 4, 5}, and j belongs to {1, 2, 3, 4, 5 };

step 3, carrying out ith atom projection, and when the alkali metal atoms of the alkali metal atom source 104 pass through the positions of the first pair of Raman lasers (201 and 204), sequentially providing three pairs of laser pulses by the first pair of Raman lasers (201 and 204), wherein the time interval of the three pairs of laser pulses is t_j＝t₀+(j-1)δt₀，t₀For an initial time interval, δ t₀Turning off the second pair of Raman lasers and the third pair of Raman lasers for time interval increment to construct a Mach-Zehnder interferometer with different chirp rates alpha_i＝(i-1)×δα+α₀Scanning Raman laser frequency difference delta omega, wherein delta alpha is chirp rate increment and alpha₀For the initial chirp rate, when an alkali metal atom of the alkali metal atom source 104 reaches the photodetector 103, an output signal P of the photodetector 103 is recorded_jiFitting the interference fringes to obtain the time interval t_j(first interference time) and phase phi (alpha)_jLinear function relationship phi (alpha) with chirp rate alpha_j＝A_j+B_jX α; wherein A is_jAnd B_jAre all fitting coefficients.

step 6, calculating AG_q＝(A_(q-1)-A_q)/(B_q-B_(q-1)) (q is an average value of 2, 3, 4, 5), and this average value is represented as α_gQ is greater than or equal to 2 and less than or equal to the total number of interval times;

step 7, performing the nth second interference time TS_nSetting, TS_n＝TS₀+ (n-1). times.delta.TS, wherein TS₀Setting the initial value of n as 1, where n is the number of times set for the second interference time, and n belongs to {1, 2, 3, 4, 5} in this embodiment; δ TS is a second interference time increment, and defines that the X-axis passes through the center of the first reflecting mirror 207, the positive direction of the X-axis is parallel to the projection direction of the alkali atom casting direction on the horizontal plane, the Y-axis passes through the center of the first reflecting mirror 207, is located on the horizontal plane and is perpendicular to the X-axis, the Z-axis is perpendicular to the horizontal plane, r is the Y-axis deflection frequency, and the initial value of r is 1.

From the initial state of the first raman mirror, the first mirror 207 is deflected for the r-th time by taking the Y-axis as a rotation axis, the direction of each deflection is the same, and the angle of each deflection is δ θ Y, wherein r is the deflection time of the Y-axis, and r belongs to {1, 2, 3, 4, 5} in the embodiment; the second raman laser 202 is turned on, the second mirror 208 remains stationary, and the third raman laser 203 is turned off;

step 8, the frequency of the first raman laser 201 and the second raman laser 202 is at the chirp rate α_gAnd (6) scanning.

The alkali metal atom source 104 moves along the predetermined atom projection trajectory 105 under the action of the cooling laser 101, and as shown in fig. 3, it is recorded that the time when the alkali metal atom moves to the optical axis of the first raman laser 201 is T', and the time when the alkali metal atom source 104 moves to the optical axis of the second raman laser 202 is T ";

at T' -TS_nAt time/2, the first raman laser 201 pulse is emitted to split the beam of the alkali metal atom source 104. First ground state |301 in a split source 104 of alkali atoms>The source of alkali metal atoms 104 continues along a first path, i.e. the first ground state |311 in fig. 3>Second ground state |302 in the split alkali metal atom>Continues along a second path, i.e., a second ground state |322 of fig. 3>；

At T' + TS_nAt time/2, a first Raman laser 201 pulse pair is emitted to be in a first path first ground state |311>Is made to transition to a first-path second ground state |312>。

At T' -TS_nAt time/2, the initial phase difference phi is transmitted₀To a second path second ground state |322 by a second raman laser 202 pulse>Is transitioned to the second path first ground state |321>；

Step 9, at T "+ TS_nAt time/2, the phase difference φ (r, TS) of the second Raman laser 202 is adjusted_nM) is phi₀+m×δφ，φ₀For the initial phase difference, the initial value of the cycle parameter m is 1, delta phi is the phase difference increment, the second Raman laser 202 pulse is emitted, and the first ground state |321 | of the second path>And a first path second ground state |312>The beam combination is carried out, the detection laser 102 and the photoelectric detector 103 are opened, and the output signals P (r, TS) of the photoelectric detector 103 are recorded_n，m)；

Step 10, increasing m by 1, repeating the step 7 to the step 9 until all m (in the embodiment, m belongs to { 1-5 }) is traversed to obtain the deflection times r and the interference time TS of the same Y axis_nUnder the condition of (d), the output signals P (r, TS) corresponding to different m_n，m)；

Step 11, output signals P (r, TS) of the photodetector 103 obtained in step 7-10_nM) phase difference phi (r, TS) from the corresponding second raman laser 202_nM) to obtain the output signal P (r, TS) of the photodetector 103_nM) is 0, and the phase difference phi (r, TS) of the second Raman laser 202_n)；

step 13, increasing n by 1, and repeating the steps 7-12 until n is traversed;

step 14, recording N as a second interference time TS_nThe set total number of times, calculate theta_k＝(C_(k+1)-C_k)/(D_k-D_(k+1)) (k is in the range of {1 to (N-1) }) average value, θ_kThe average value of (D) is recorded as the Y-axis deflection angle theta_12y；

Step 15 initial shape from first mirror 207The first mirror 207 is deflected by a Y-axis deflection angle theta in the deflection direction in step 7 with the Y-axis as the rotation axis_12y. The first mirror 207 is in the Y-axis deflection adjustment final state.

Adjusting the final state of the Y-axis deflection from the first mirror 207, deflecting the first mirror 207 for the w-th time by taking the X-axis as a rotation axis, wherein the direction of each deflection is the same, the angle of each deflection is δ θ X, and w is the number of times of X-axis deflection, in this embodiment, w is for {1, 2, 3, 4, 5}, the second raman laser 202 is turned on, the second mirror 208 is kept still, and the third raman laser 203 is turned off;

selecting the TS set for the last time in the step 8_nI.e. n is 5, repeat step 8 at T "+ TS_nAt time/2, the phase difference φ (w, TS) of the second Raman laser 202 is adjusted_nM1) is phi₀+ m1 × δ φ, with the initial value of the cycling parameter m1 being 1, a second Raman laser 202 pulse is emitted to first ground state |322 for the second path>And a first path second ground state |312>The detection laser 102 and the photodetector 103 are turned on, and the output signal P (w, TS) of the photodetector 103 is recorded_n，m1)；

Step 16, increasing 1 to m1, and repeating step 15 until all m1 (m 1 belongs to { 1-5 } in the embodiment) are traversed to obtain the same X-axis deflection times w and the same interference time TS_nUnder the condition (2), the output signals P (w, TS) corresponding to different m1_n，m1)；

Step 17, increasing the X-axis deflection times w by 1, repeating steps 15 to 16 until all the X-axis deflection times w are traversed, and performing sine fitting to obtain the contrast C corresponding to different deflection angles w × δ θ X (w is 1, 2, 3, 4, 5)_w(W ═ 1, 2, 3, 4, 5), for C_w(w is 1, 2, 3, 4, 5) and a function of the angle w × δ θ X, and obtaining an angle corresponding to the central value of the gaussian function, which is recorded as the X-axis deflection angle θ_12x；

The final state of Y-axis deflection adjustment from the first mirror 207 is to deflect the first mirror 207 by θ in the deflection direction in step 15 with the X-axis as the rotation axis_12x. The first mirror 207 is in the final deflection adjustment final state;

step 18, taking the left end of the atomic interference physical system 100 as a light outlet end, taking the right end as a projecting end, projecting an alkali metal atom source 104 from the right end to the left end in the atomic interference physical system 100, positioning a cooling laser 101 at the right end of the atomic interference physical system 100, positioning a photoelectric detector 103 at the left end of the atomic interference physical system 100, positioning a detection laser 102 at the left end of the atomic interference physical system 100, and sequentially distributing a first pair of raman lasers to a third pair of raman lasers along the left end to the right end of the atomic interference physical system 100;

the actual third raman laser is used as the first raman laser in step 7-17,

using the actual third mirror as the first mirror in step 7-17;

using the actual first Raman laser as the third Raman laser in the step 7-17;

using the actual first mirror as the third mirror in step 7-17;

repeating the steps 7-17, and sequentially measuring the actual Y-axis deflection angle theta of the third reflector 209_23yAnd X-axis deflection angle theta_23x；

Step 19 is to deflect the actual third mirror 209 by the Y-axis deflection angle θ using the Y-axis as the rotation axis from the initial state of the actual third mirror_23yAnd the third mirror 207 is deflected by an X-axis deflection angle theta about the X-axis as a rotation axis_23x；

Step 20, the alkali metal atom source 104 moves along a preset atom casting track 105 under the action of the cooling laser 101, when the alkali metal atom source 104 moves to a position away from the center of the first raman laser 201, the first raman laser 201 pulse is emitted to split the beam of the alkali metal atom source 104, when the alkali metal atom source 104 moves to a position away from the center of the second raman laser 202, the second raman laser 202 pulse is emitted to make the atoms jump between two energy levels and obtain photon momentum, when the alkali metal atom source 104 moves to a position away from the center of the third raman laser 203, the third raman laser 203 pulse is emitted to combine the atoms to form a mach-zehnder interferometer, and the atomic interference of three beams of separated raman lasers (201, 202 and 203) is realized.

The laser cooling, atom interference and phase extraction of atoms in the atom interferometer are general techniques, which are not discussed in detail in this patent.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.

Claims

1. A separated Raman laser type atomic interference gyro device comprises an atomic interference physical system (100) and is characterized in that one end of the atomic interference physical system (100) is a projecting end, the other end of the atomic interference physical system is a light emitting end, a first Raman laser (201), a second Raman laser (202) and a third Raman laser (203) are sequentially distributed on one side of the atomic interference physical system (100) from the projecting end to the light emitting end, a first reflector (207), a second reflector (208) and a third reflector (209) are sequentially distributed on the other side of the atomic interference physical system (100) from the projecting end to the light emitting end,

the cooling laser (101) is located at the projecting end of the atomic interference physical system (100), the photoelectric detector (103) is located at the light emitting end of the atomic interference physical system (100), and the detection laser (102) is located at the light emitting end of the atomic interference physical system (100).

2. The debugging method of the separated Raman laser type atomic interference gyroscope is characterized by comprising the following steps of:

step 1, an alkali metal atom source (104) moves along a preset atom casting track (105) under the action of cooling laser (101);

and 3, carrying out ith atom projection, and when the alkali metal atoms of the alkali metal atom source (104) pass through the positions of the first pair of Raman lasers, sequentially providing three pairs of laser pulses by the first pair of Raman lasers, wherein the time interval of the three pairs of laser pulses is t_j＝t₀+(j-1)δt₀，t₀Is an initialTime interval, δ t₀The second and third pairs of Raman lasers are turned off for time interval increments at different chirp rates alpha_i＝(i-1)×δα+α₀Scanning Raman laser frequency difference delta omega, wherein delta alpha is chirp rate increment and alpha₀For the initial chirp rate, when an alkali metal atom of an alkali metal atom source (104) reaches a photodetector (103), an output signal P of the photodetector (103) is recorded_jiFitting the interference fringes to obtain the time interval t_jUnder the condition of phase phi (alpha)_jLinear function relationship phi (alpha) with chirp rate alpha_j＝A_j+B_jX α; wherein A is_jAnd B_jAre all fitting coefficients;

step 7, performing the nth second interference time TS_nSetting, TS_n＝TS₀+ (n-1). times.delta.TS, wherein TS₀Setting the initial second interference time, wherein n is the number of times set for the second interference time, the initial value of n is 1, and δ TS is the second interference time increment, and defining that an X axis passes through the center of a first reflector (207), the positive direction of the X axis is parallel to the projection direction of the alkali atom projection direction on a horizontal plane, a Y axis passes through the center of the first reflector (207), is positioned on the horizontal plane and is vertical to the X axis, a Z axis is vertical to the horizontal plane, r is the deflection number of times of the Y axis, and the initial value of r is 1;

from the initial state of the first Raman mirror, the first mirror (207) deflects for the r times by taking the Y axis as a rotating shaft, the deflection direction of each time is the same, the deflection angle of each time is delta theta Y, wherein r is the deflection times of the Y axis; the second Raman laser (202) is turned on, the second mirror (208) is kept still, and the third Raman laser (203) is turned off;

step 8, the frequency of the first Raman laser (201) and the second Raman laser (202) is determined by the chirp rate alpha_gThe scanning is carried out by scanning the object,

an alkali metal atom source (104) moves along a preset atom casting track (105) under the action of cooling laser (101), and the time when the alkali metal atom moves to the optical axis of the first Raman laser (201) is recorded as T ', and the time when the alkali metal atom source (104) moves to the optical axis of the second Raman laser (202) is recorded as T';

at T' -TS_nAt the time of/2, emitting a first Raman laser (201) pulse to split the beam of the alkali metal atom source (104), wherein the split alkali metal atom source (104) in the first ground state continues to move along a first path, and the split alkali metal atom in the second ground state continues to move along a second path;

at T' + TS_nAt a time point/2, emitting a first Raman laser (201) pulse to make the transition of the alkali metal atom in the first path first ground state to the first path second ground state,

at T' -TS_nAt time/2, the initial phase difference phi is transmitted₀The second Raman laser (202) pulse of the second path transits the alkali metal atom of the second ground state to the second path first ground state;

step 9, at T "+ TS_nAt time/2, the phase difference phi (r, TS) of the second Raman laser (202) is adjusted_nM) is phi₀+m×δφ，φ₀For initial phase difference, the initial value of the cycle parameter m is 1, delta phi is phase difference increment, a second Raman laser (202) pulse is emitted, the first ground state of the second path and the second ground state of the first path are combined, the detection laser (102) and the photoelectric detector (103) are opened, and output signals P (r, TS) of the photoelectric detector (103) are recorded_n，m)；

Step 11, output signal P (r, TS) of the photoelectric detector (103) obtained in the step 7-10_nM) andthe phase difference phi (r, TS) of the corresponding second Raman laser (202)_nM) obtaining the output signal P (r, TS) of the photodetector (103) by fitting_nM) is 0, and the phase difference phi (r, TS) of the second Raman laser (202)_n)；

step 13, increasing n by 1, and repeating the steps 7-12 until n is traversed;

Step 15, from the initial state of the first mirror 207, deflecting the first mirror 207 by a Y-axis deflection angle theta in the deflection direction in step 7 with the Y-axis as the rotation axis_12yThe first mirror (207) is in the final state of Y-axis deflection adjustment,

adjusting a final state through Y-axis deflection of the first reflecting mirror (207), deflecting the first reflecting mirror (207) for the w-th time by taking an X-axis as a rotating shaft, wherein the direction of each deflection is the same, the angle of each deflection is delta theta X, w is the number of times of X-axis deflection, the second Raman laser (202) is opened, the second reflecting mirror (208) is kept still, and the third Raman laser (203) is closed;

selecting the TS set for the last time in the step 8_nRepeat step 8 at T "+ TS_nAt time/2, the phase difference phi (w, TS) of the second Raman laser (202) is adjusted_nM1) is phi₀+ m1 × δ Φ, the initial value of the cyclic parameter m1 being 1, emitting a second raman laser (202) pulse, combining alkali metal atoms of the first ground state of the second path and the second ground state of the first path, turning on the detection laser (102) and the photodetector (103), and recording the output signal P (w, TS) of the photodetector (103)_n，m1)；

Step 16, increasing m1 by 1, repeating step 15 until all m1 are traversed, and obtaining the same X-axis deflection times w and the same interference time TS_nUnder the condition (2), the output signals P (w, TS) corresponding to different m1_n，m1)；

The final state of Y-axis deflection adjustment from the first mirror (207) is adjusted by deflecting the first mirror (207) in the deflection direction in step 15 by theta about the X-axis as the rotation axis_12xThe first mirror (207) is in a final state of final deflection adjustment.