CN107607890B - Raman spectrum-based rapid magnetic field measurement method and device - Google Patents
Raman spectrum-based rapid magnetic field measurement method and device Download PDFInfo
- Publication number
- CN107607890B CN107607890B CN201710812881.0A CN201710812881A CN107607890B CN 107607890 B CN107607890 B CN 107607890B CN 201710812881 A CN201710812881 A CN 201710812881A CN 107607890 B CN107607890 B CN 107607890B
- Authority
- CN
- China
- Prior art keywords
- raman
- magnetic field
- raman spectrum
- atom
- frequency
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
- Spectrometry And Color Measurement (AREA)
Abstract
The invention discloses a rapid magnetic field measurement method and a device based on Raman spectrum, the method comprises the following steps: s1, Raman spectrum measurement: preparing cold radicals; throwing or free-falling the cold atomic groups, utilizing the interaction of Raman pi pulses and atoms after the atoms enter a vacuum cavity to be tested, and measuring Raman spectrums at different action positions in the vacuum cavity to be tested to obtain Raman spectrum data corresponding to each action position; s2, Raman spectrum fitting: fitting each group of Raman spectrum data by using a composite pull ratio function to obtain the resonance frequency of the Raman spectrum corresponding to each action position; s3, magnetic field intensity calculation: calculating the magnetic field intensity of each target position by using the resonance frequency of the obtained Raman spectrum; the device comprises a Raman spectrum measurement module, a Raman spectrum fitting module and a magnetic field intensity calculation module. The invention can realize the rapid magnetic field measurement based on the Raman spectrum and has the advantages of simple realization method and high measurement precision.
Description
Technical field
The present invention relates to magnetic field measurement technology field more particularly to a kind of quick magnetic field measurement method based on Raman spectrum and
Device.
Background technology
Magnetic field measurement technology has a wide range of applications in each field such as biomedical, military technology and industry.For
Magnetic-field measurement, presently, there are many measuring methods, including electromagnetic induction method, fluxgate method, Hall effect method, superconductivity effects method with
And Pumping Magnetic Resonance Method etc., wherein due under the saturation activation of alternating magnetic field, be in tested magnetic field the magnetic induction intensity of magnetic core with
There are non-linear relation between the magnetic field intensity in tested magnetic field, fluxgate method is to be measured using the characteristic；Hall effect
Method is to measure magnetic field using Hall effect, and Hall effect is when external magnetic field is perpendicular to the electric current flowed through in metal or semiconductor
When, in metal or semiconductor electromotive force can be generated perpendicular to the direction of electric current and external magnetic field；Pumping Magnetic Resonance Method is to utilize amount of substance
Sub- state change measures magnetic field.It is usually necessary to use different Measurement Method for Magnetic Field under different occasions, as fluxgate method is usual
For measuring constant or slowly varying low-intensity magnetic field, Hall effect method is for measuring small―gap suture magnetic field, and Pumping Magnetic Resonance Method is for surveying
Measure uniform stationary magnetic field.Above-mentioned measurement method measurement process is complicated, more demanding to measuring environment, cannot meet field simultaneously
The measurement demand of all kinds of measuring environments such as measurement, and by being based on manual measurement mode, measurement efficiency is low, easy tos produce measurement
Error.
The magnetic field intensity of any position can be measured using Raman spectrum, measurement process is simple, measurement range is big and measures essence
Degree is high, but when current measurement Raman spectrum, is typically based on manual measurement mode, i.e., by artificial constantly regulate Raman optical frequency
The measurement parameters such as rate, action time are to get Raman spectrum, and measurement process is inconvenient, measurement efficiency is low, while needing to grow very much
Time of measuring, and in longer time of measuring, measurement result is very easy to be influenced to generate measurement error by magnetic field drift.This
Outside, when handling Raman modal data, the determination of resonant frequency is mainly fitted or extracts maximum value process using unimodal at present,
This can increase the complexity of data handling procedure, extend data processing time, increases magnetic-field measurement error.
Invention content
The technical problem to be solved in the present invention is that：For technical problem of the existing technology, the present invention provides one
Kind can be based on Raman spectrum realizes that quick magnetic field measures, and implementation method is simple, high certainty of measurement based on the quick of Raman spectrum
Measurement Method for Magnetic Field and device.
In order to solve the above technical problems, technical solution proposed by the present invention is：
A kind of quick magnetic field measurement method based on Raman spectrum, step include：
S1. Raman spectrometry：Prepare cold atom cloud；By cold atom cloud upthrow or free-falling, when atom enter it is to be measured true
Raman π pulses and atomic interaction are utilized after cavity, and measures the Raman spectrum in vacuum chamber to be measured at different role position, are obtained
To the Raman modal data of each active position of correspondence；
S2. Raman spectrum is fitted：Each group Raman modal data is fitted using compound Lapie's function respectively, is obtained corresponding each
The resonant frequency of the Raman spectrum of active position；
S3. magnetic field intensity calculates：Respectively each target location is calculated using the resonant frequency of the obtained Raman spectrum
Magnetic field intensity.
As being further improved for the method for the present invention, Raman modal data is fitted described in every group in the step S2 tool
Body step is：
S21. the Raman modal data obtained is divided into three sections, extracts each segment data Central Plains of the Raman modal data respectively
The maximum value of sub- transition probability and corresponding Raman light frequency；
S22. the maximum value of atomic transition probabilities described in each segment data based on extraction and corresponding Raman optical frequency
Rate is fitted using Raman modal data described in every group of compound Lapie's function pair, obtains three resonance of current Raman modal data
Frequency.
As being further improved for the method for the present invention, in the step S21 specifically by Raman modal data described in each group according to
Wave crest is divided into three sections, and Raman modal data carries out described in every group of compound Lapie's function pair of the specifically used following formulas of step S22
Fitting；
Wherein, P1For atomic transition probabilities；A-1、A0、A1Respectively fitting Raman spectrum is finally obtained corresponds to mFState atom
Transition peak heights, mF=-1,0,1, and initial value is respectively to extract corresponding to mFThe maximum value of the atomic transition probabilities of state；
ω-1、ω0、ω1Respectively correspond to mFThe resonant frequency of state atom, and the atomic transition probabilities that initial value respectively extracts are most
The corresponding Raman light frequency of big value, ΩeffFor effective Rabi frequency of Raman pulse,Respectively Raman
Light is to mFThe difference optical frequency shift that state atom generates, δDFor effective Doppler frequency shift, τ is Raman pulse operating time.
As being further improved for the method for the present invention, the step S3 the specific steps are：
S31. it is drawn according to the fitting under Left-hand circular polarization raman laser, right-hand circular polarization raman laser at target effect site
Three resonant frequencies of graceful spectrum, and the difference of first, third resonant frequency in three resonant frequencies is calculated separately, obtain resonance frequency
Rate is poor；
S32. the magnetic field intensity B of Left-hand circular polarization state is calculated according to the difference in resonance frequencies respectivelyIt is left, dextrorotation circle it is inclined
The magnetic field intensity B for state of shakingIt is right；
S33. according to the magnetic field intensity B of the Left-hand circular polarization stateIt is left, right-hand circular polarization state magnetic field intensity BIt is rightIt calculates
Obtain the absolute magnetic field strengths at target effect site
As being further improved for the method for the present invention, the step S1 the specific steps are：
S11. cold atom cloud is prepared；
S12. by the cold atom cloud upthrow of preparation or free-falling；
S13. two beam raman lasers and atomic interaction are utilized after atom enters vacuum chamber to be measured so that atomic group produces
Raw Raman transition；
S14. the transition probability of Measurement atom；
S15. the relative frequency for scanning two beam raman lasers, repeats step S11~S15, until obtaining current effect
Raman spectrum at position；
S16. the time of delay Raman π pulses and atom effect, step S11~S16 is repeated, until obtaining to be measured true
Raman spectrum in cavity at different role position.
As being further improved for the method for the present invention, in the step S11 specifically in Magneto-Optical Trap, by adjusting Magneto-Optical Trap
Parameter prepare on the atomic state in F=2, the cold atom cloud of the μ k of temperature≤10.
As being further improved for the method for the present invention：The Raman π pulses are specifically less than the short pulse of 2ms；The step
The frequency domain that frequency sweep stepping when scanning Raman light in rapid S14 is less than Raman pulse broadens, and swept frequency range when scanning Raman light is big
In atom single order Zeeman frequency displacement.
As being further improved for the method for the present invention, the step S14 the specific steps are：Arrangement is for detecting original in advance
The detection cavity of sub- state, when atom passes through detection cavity, after opening detection light and persistently specifying long-time, measurement is currently at F=2
The atomicity N of state2, it is spaced after presetting first time and the atom in F=1 states is returned into pump to F=2 states, and at default second
Between after be again turned on detection light, it is N to measure the total atom number in F=1 states and F=2 states in current atomic group1+N2, according to P1
=1-N2/(N1+N2) transition probability of atom is calculated.
The present invention further discloses a kind of automatic magnetic field measuring device, including：
Raman spectrum measurement module, including vacuum chamber to be measured, be used to prepare and imprison cold atom cloud Magneto-Optical Trap component, be used for
Generate two beam raman lasers, and frequency to two beam raman lasers and phase controlled raman laser system, for detecting
The atomic state detection system of the transition probability of atom in atomic group, and for controlling Magneto-Optical Trap capture, release or upthrow atom
Group, control raman laser and the time of atomic group effect and the sequential control system of the detection of atom final states；Prepare cold atom
After group, upthrow or free-falling in vacuum chamber to be measured by the atomic group of preparation, using two beam Raman lights and atomic interaction,
And the Raman spectrum in vacuum chamber to be measured at different role position is measured, obtain the multigroup Raman modal data for corresponding to each active position；
Raman spectrum fitting module is obtained for being respectively fitted each group Raman modal data using compound Lapie's function
The resonant frequency of the Raman spectrum of corresponding each active position；
Magnetic field intensity calculates module, for calculating each target location using the resonant frequency of the obtained Raman spectrum respectively
The magnetic field intensity at place.
As being further improved for apparatus of the present invention：It is provided with quantization field coil in the vacuum chamber to be measured, uses
In generation quantum magnetizing field；The cold atom cloud prepared in the Magneto-Optical Trap component is on the atomic state of F=2, the μ of and temperature≤10
k。
Compared with the prior art, the advantages of the present invention are as follows：
1) the present invention is based on the quick magnetic field measurement methods and device of Raman spectrum, different in vacuum chamber to be measured acquiring
After the Raman spectrum of position, it is fitted using compound Lapie's function pair Raman modal data, is calculated by obtained fitting Raman spectrum
To the magnetic field intensity of different location, without manually participating in can be realized the automatic measurement in magnetic field, while it being based on compound Lapie's function
Once fitting is only needed when being fitted to Raman modal data, compared to traditional side based on unimodal fitting or extraction maximum value process
Formula can greatly reduce data processing amount while ensureing measurement accuracy, data-handling efficiency be improved, to effectively improve
Magnetic-field measurement efficiency realizes that quick magnetic field measures；
2) the present invention is based on the quick magnetic field measurement methods and device of Raman spectrum, by preparing cold atom cloud and to be measured true
So that Raman pulse is interacted with atomic group in cavity, is swept in combination with raman laser frequency scanning and magnetic field space target location
The mode retouched measures the Raman spectrum at different location in vacuum chamber to be measured, can realize entire interference based on two-dimensional scan mode
The automatic measurement in intracavitary magnetic field can be realized magnetic-field measurement without manually participating in, and can be used based on two-dimensional scan automatically
Short pulse, the scan mode of long stepping, greatly improve measurement efficiency；
3) the present invention is based on the quick magnetic field measurement methods and device of Raman spectrum, and processing is fitted to every group of Raman spectrum
When, Raman modal data is divided into three sections first, the maximum value of atomic transition probabilities and corresponding in extracting per segment data
Raman light frequency is fitted using every group of Raman modal data of compound Lapie's function pair, can be integrated atom in every segment data and be jumped
It moves the maximum value of probability and corresponding Raman light frequency carrys out Efficient Characterization Raman spectrum, once fitting can provide three resonance frequencies
Rate eliminates common-mode error and greatly reduces data processing amount without being handled three times Raman modal data.
Description of the drawings
Fig. 1 is the detailed implementation process schematic diagram of quick magnetic field measurement method of the present embodiment based on Raman spectrum.
Fig. 2 is the first structural principle signal for the device that quick magnetic field measurement method is realized in the specific embodiment of the invention
Figure.
Fig. 3 is second of structural principle signal for the device that quick magnetic field measurement method is realized in the specific embodiment of the invention
Figure.
Specific implementation mode
Below in conjunction with Figure of description and specific preferred embodiment, the invention will be further described, but not therefore and
It limits the scope of the invention.
As shown in Figure 1, quick magnetic field measurement method step of the present embodiment based on Raman spectrum includes：
S1. Raman spectrometry：Prepare cold atom cloud；By cold atom cloud upthrow or free-falling, when atom enter it is to be measured true
Raman π pulses and atomic interaction are utilized after cavity, and measures the Raman spectrum in vacuum chamber to be measured at different role position, are obtained
To the Raman modal data of each active position of correspondence.
The present embodiment specifically in vacuum chamber to be measured cold atom cloud prepared using Magneto-Optical Trap and make atomic group upthrow (by
It is lower upward) or free released movement, it is realized by the parameter of optimizing regulation Magneto-Optical Trap, such as laser power, balance, sequential ginseng
Number, so that cold atom is on the atomic state of F=2, and make atomic group temperature≤10 μ k to obtain cold atom cloud.
The present embodiment step S1 the specific steps are：
SS11. cold atom cloud is prepared；
S12. by the cold atom cloud upthrow of preparation or free-falling；
S13. two beam raman lasers and atomic interaction are utilized after atom enters vacuum chamber to be measured so that atomic group produces
Raw Raman transition；
S14. the transition probability of Measurement atom；
S15. the relative frequency for scanning two beam raman lasers, repeats step S11~S15, until obtaining current effect
Raman spectrum at position；
S16. the time of delay Raman π pulses and atom effect, step S11~S16 is repeated, until obtaining to be measured true
Raman spectrum in cavity at different role position.
The present embodiment specifically generates two beam raman lasers first, reuses the frequency that optical phase-locked loop locks two beam raman lasers
Rate and phase are adjusted the Raman light of generation specifically used with generating the Raman light for making cold atom cloud that Raman transition occur
Radio frequency attenuator, with by adjust Raman light generate needed for size Raman pulse, adjustment process is particular by being arranged two beams
The power of raman laser is a certain steady state value, recycles the power that electronics reponse system stablizes raman laser to realize, walks in detail
Suddenly it is：The action time of scanning and the Raman π pulses of atomic interaction generates Lapie's concussion, if Lapie's concussion period is big
In or be less than predetermined threshold value, then the radio-frequency driven power for adjusting Raman light acousto-optic modulator tunes up the power of two beam raman lasers
Or turn down it is a certain amount of, again obtain Lapie concussion, until Lapie shake the period be equal to predetermined threshold value until, Raman can be obtained at this time
The duration of π pulses is required size, and when such as required Raman π pulses are 1ms, then Lapie is shaken the predetermined threshold value in period and can be set
It is set to 2ms.
The specifically used short pulse less than 2ms of the present embodiment Raman π pulses, i.e. the pulse duration within 2ms, preferably
For 1ms, compared to using long pulse to need very small scanning stepping, the present embodiment combination two-dimensional scan mode, by using
Short pulse less than 2ms, correspondence can use big frequency sweep stepping, the time required to can greatly shortening measurement, improve and measure
Efficiency measurement.When frequency sweep stepping when the present embodiment scans Raman light is arranged, the frequency domain broadening less than Raman pulse is specifically taken, such as
Frequency domain broadening may be set to take 400Hz when being 1kHz, and swept frequency range when scanning Raman light is more than atom single order Zeeman frequency displacement, energy
While enough improving measurement efficiency, ensure scanning accuracy.
In the present embodiment, step S14 the specific steps are：Detection cavity of the arrangement for Measurement atom state in advance, works as atom
When by detection cavity, after opening detection light and persistently specifying long-time, the atomicity N for being currently at F=2 states is measured2；Interval is pre-
It, specifically can be by applying back pump light so that F=1 states will be in if the atom in F=1 states, which is returned pump, after first time arrives F=2 states
Atom return pump arrive F=2 states；It waits for and is again turned on detection light after presetting for the second time, measure and be in F=1 in current atomic group
The total atom number of state and F=2 states is N1+N2, according to the following formula (1) transition probability of atom is calculated；
P1=1-N2/(N1+N2) (1)
It can implement the standardization detection of atomic state when cold atom cloud falls after rise and again passes by detection cavity through the above steps
Process realizes the normalization of the transition probability of atom, and detection accuracy is high.Above-mentioned first time, the second time can be according to realities
Photodetector can be used to realize in border demand setting, atomicity measurement.
The present embodiment generates the Raman light of Left-hand circular polarization first, and Left-hand circular polarization is obtained according to above-mentioned steps S11~S16
The Raman spectrum of each target location is corresponded under state, then the polarization direction of Raman light is adjusted into 180 degree to generate right-hand circular polarization
Raman light, repeat step S11~S16, then can obtain the Raman for corresponding to each target location under right-hand circular polarization state
Spectrum, that is, acquire the Raman spectrum in interference cavity at each active position under different polarization state, can be further by the Raman spectrum
Calculate the magnetic field intensity of each active position in interference cavity.
The present embodiment uses the above method, by preparing cold atom cloud and making in vacuum chamber to be measured Raman pulse and atom
Group's interaction measures vacuum to be measured in combination with the mode of raman laser frequency scanning and the scanning of magnetic field space target location
Raman spectrum at intracavitary different location can realize the automatic measurement in magnetic field in entire interference cavity based on two-dimensional scan mode,
Without manually participating in realize that magnetic-field measurement, measurement efficiency and precision are high automatically, and short arteries and veins can be used based on two-dimensional scan
The scan mode of punching, long stepping, greatly improves measurement efficiency, and obtained magnetic-field measurement precision is high；This implementation is used simultaneously
The example above method, measurement process part is simple, needs not rely upon complicated measuring condition and magnetic field automatic measurement, Ke Yifang can be realized
Just suitable for all kinds of measuring environments such as laboratory and field measurement.
S2. Raman spectrum is fitted：It is fitted, is obtained pair using compound Lapie's function according to by each group Raman modal data respectively
Answer the resonant frequency of the Raman spectrum of each active position.
The present embodiment is after step S1 acquires the Raman modal data of different location in vacuum chamber to be measured, to Raman spectrum number
According to being fitted, the resonant frequency of the Raman spectrum obtained by fitting calculates to obtain the magnetic field intensity of different location, without artificial ginseng
With the automatic measurement that magnetic field can be realized；Determination tradition to Raman spectrum resonant frequency is directly to use unimodal fitting or extraction
Maximum value process, but unimodal fitting or extraction maximum value process can increase the complexity of data handling procedure, extend at data
The time is managed, while increasing magnetic-field measurement error, using based on compound Lapie's function when the present embodiment is fitted Raman modal data
Mode can realize once fitting compared to traditional mode for being directly based upon whole unimodal fitting or extraction maximum value process,
Data processing amount can greatly be reduced while ensureing measurement accuracy, data-handling efficiency is improved, to effectively improve magnetic
Field measurement efficiency realizes that high-precision quick magnetic field measures, it may be convenient to be applied to for rings such as laboratory and field measuremenies
In border.
In the present embodiment, in step S2 every group of Raman modal data be fitted the specific steps are：
S21. the maximum value of atomic transition probabilities and corresponding drawing in each segment data of extraction Raman modal data respectively
Graceful light frequency；
S22. in each segment data based on extraction atomic transition probabilities maximum value and corresponding Raman light frequency, make
It is fitted with every group of Raman modal data of compound Lapie's function pair, obtains three resonant frequencies of current Raman modal data.
Raman modal data is Raman light frequency and the transition probability corresponding relation data of atom, every group of Raman modal data
X coordinate is raman laser frequency, and y-coordinate is corresponding transition probability, when being fitted processing to every group of Raman spectrum, will be drawn first
Graceful modal data is divided into multistage, in extracting per segment data corresponding to the maximum value of atomic transition probabilities and maximum transition probability
Raman light frequency, the transition peak heights of the atom based on extraction, resonant frequency use every group of Raman spectrum number of compound Lapie's function pair
According to being fitted, the maximum value of atomic transition probabilities and corresponding Raman light frequency in every segment data can be integrated and carry out Efficient Characterization
Raman spectrum, and without handling all Raman modal datas, greatly reduce required data processing amount.
It is specifically each group Raman modal data to be divided into three sections, and use compound Lapie's letter of following formula (2) in the present embodiment
It is several that every group of Raman modal data is fitted；
Wherein, P1For atomic transition probabilities；A-1、A0、A1What respectively fitting Raman spectrum finally obtained corresponds to mFState atom
Transition peak heights, mF=-1,0,1, and initial value is respectively to correspond to mFThe maximum value of the atomic transition probabilities of state；ω-1、
ω0、ω1Respectively fitting Raman spectrum is finally obtained corresponds to mFThe resonant frequency of state, and initial value is respectively to correspond to mFState
Raman light frequency corresponding to the maximum value of atomic transition probabilities；ΩeffFor effective Rabi frequency of Raman pulse, andWithEffective Lapie of respectively i-th (i=1,2) beam raman laser
Frequency and the i-th beam raman laser are to mFThe exchange Stark Shift that state atom generates, Δ are that single photon loses tiltedly,Respectively Raman light is to mFThe difference optical frequency shift that state atom generates, andδDTo have
Doppler frequency shift is imitated, τ is Raman pulse operating time.
S3. magnetic field intensity calculates：The magnetic field of each target location is calculated using the resonant frequency of obtained Raman spectrum respectively
Intensity.
In the present embodiment, step S3 the specific steps are：
S31. it is drawn according to the fitting under Left-hand circular polarization raman laser, right-hand circular polarization raman laser at target effect site
Three resonant frequencies of graceful spectrum, calculate separately the difference of first, third resonant frequency in three resonant frequencies, obtain resonant frequency
Difference；
S32. the magnetic field intensity B of Left-hand circular polarization state is calculated according to difference in resonance frequencies respectivelyIt is left, right-hand circular polarization shape
The magnetic field intensity B of stateIt is right；
S33. according to the magnetic field intensity B of Left-hand circular polarization stateIt is left, right-hand circular polarization state magnetic field intensity BIt is rightIt is calculated
Absolute magnetic field strengths at target effect siteTo eliminate the influence of optical frequency shift.
In the present embodiment, three peak frequencies of Raman spectrum are labeled as ω successively-1,ω0,ω1, difference in resonance frequencies is specific
Take the difference ω between first, third resonant frequency1-ω-1, then the magnetic field intensity B of Left-hand circular polarization stateIt is left, right-hand circular polarization
The magnetic field intensity B of stateIt is rightFormula concretely：
Wherein, (ω1,1-ω-1,-1)Left (right side)The resonance that fitting Raman spectrum is obtained under respectively left (right side) rounding polarization configuration
Difference on the frequency, γ1=2 π 1.4MHz/G are that 1 rank matches graceful coefficient.
Absolute magnetic field strengthsCalculation formula be specially：
The absolute magnetic field strengths in vacuum chamber to be measured at different location can be calculated through the above steps, entirely measured
Journey may not need artificial participation, and the magnetic field of different location in entire vacuum chamber can be realized in the generation sequential by controlling Raman light
It measures.
As shown in Figure 1, the detailed step that the fitting of step S2 Raman spectrums and step S3 magnetic field intensities calculate in the present embodiment is：
1. reading the total m groups of Raman modal data at different measurement positions, the x coordinate of every group of data is raman laser frequency, y
Coordinate is corresponding transition probability；
2. every group of data are divided into 3 sections, and the maximum value y of each segment data is sought respectivelypAnd its corresponding abscissa xp,
Middle p=-1,0,1, setting initial value i=1；
3. being fitted using such as i-th group of Raman modal data of compound Lapie's function pair of above formula (2), three spectral peaks are obtained
Frequency coordinate fpAnd its fitting uncertainty Ufp, wherein p=-1,0,1；
4. magnetic field intensity B is calculated according to formula (3), (4)iAnd its uncertainty of measurement UBi, and it is deposited into measurement knot
In fruit array Bdata；
5. enable i=i+1, repeat step 3. -5., until end loop when i=m；
6. exporting and showing the m magnetic field value Bdata measured at position.
The device of the automatic Measurement Method for Magnetic Field of the present embodiment, including：
Raman spectrum measurement module, including vacuum chamber to be measured, be used to prepare and imprison cold atom cloud Magneto-Optical Trap component, be used for
Generate two beam raman lasers, and frequency to two beam raman lasers and phase controlled raman laser system, for detecting
The atomic state detection system of the transition probability of atom in atomic group, and for controlling Magneto-Optical Trap capture, release or upthrow atom
Group and control raman laser and the time of atomic group effect and the sequential control system of the detection of control atom final states；System
After standby cold atom cloud, upthrow or free-falling in vacuum chamber to be measured by the atomic group of preparation utilize two beam Raman lights and atom
Interaction, and the Raman spectrum in vacuum chamber to be measured at different role position is measured, obtain the multigroup drawing for corresponding to each active position
Graceful modal data；
Raman spectrum fitting module, for being fitted respectively using compound Lapie's function according to by each group Raman modal data,
Obtain corresponding to the resonant frequency of the Raman spectrum of each active position；
Magnetic field intensity calculates module, for calculating each target location using the resonant frequency of obtained Raman spectrum respectively
Magnetic field intensity.
In the present embodiment, quantization field coil is provided in vacuum chamber to be measured, for generating quantum magnetizing field；Magneto-optic
The cold atom cloud prepared in trap component is specifically on the atomic state of F=2, the μ k of and temperature≤10.
It is as shown in Figure 2,3 the concrete structure of Raman spectrum measurement module in the specific embodiment of the invention, that is, specifically includes：
Magneto-Optical Trap component is used to prepare and imprisons cold atom cloud；
Vacuum chamber to be measured；
Quantization field coil is arranged outside vacuum chamber to be measured, for generating quantum magnetizing field；
Raman laser system for generating two beam raman lasers, and is controlled the frequency and phase of two beam raman lasers
System；
Atomic state detection system, the transition probability for atom in Measurement atom group；
And sequential control system, for controlling Magneto-Optical Trap capture, release or upthrow atomic group, raman laser and atomic group
The time of effect and the detection of atom final states.
The present embodiment corresponds to make as shown in Figure 2 by Magneto-Optical Trap preparation, upthrow (or freely discharging) cold atom cloud
Magnetic-field measurement is realized when throwing cold atom cloud, magnetic-field measurement is realized when such as Fig. 3 corresponding to that cold atom cloud is made freely to discharge, wherein preparing
Cold atom cloud be on the atomic state of F=2, the temperature of atomic group is specifically set as true in≤10 μ k and vacuum chamber
Reciprocal of duty cycle is set as being better than 10-7Pa；Quantization field coil is specifically made of long solenoid, and vacuum chamber to be measured is uniformly wound on
Outside generates quantum magnetizing field in vacuum chamber to be measured, and the quantum magnetizing field size of generation is directly proportional to the electric current applied, magnetic
Field direction is specifically determined by the direction of input current, such as straight down or upwards.
The time of the capture of the present embodiment Magneto-Optical Trap, release or upthrow atomic group and Raman π pulses and atomic group effect with
And the detection etc. of atom final states is specifically controlled by sequential control system, can be realized in vacuum chamber without manually participating in
The automatic measurement in magnetic field measures efficiently compared to manual measurement and precision is high.Specifically use can provide multichannel mould to control unit
The controller of quasi-/digital signal and TTL trigger signals, and two or more sweep parameters can be further arranged by control,
Make it possible to easily realize automatically controlling for entire measurement sequential.
General power >=the 10mW for the raman laser that the present embodiment raman laser system generates, the diameter of raman laser >=
20mm, raman laser system further include radio frequency attenuator and optical phase-locked loop, and the Raman light generated is adjusted by radio frequency attenuator
Size carries out accurate lock by the frequency and phase of two beam raman laser of optical phase-locked loop pair.
In the present embodiment, it is saturating that atomic state detection system specifically includes detection light, time pump light, optical mirror, optical imagery
Mirror and photoelectric detecting system, optical mirror are located at detection light incident direction in the other side of vacuum window, and optical imagery is saturating
Mirror and photoelectric detecting system perpendicular to detection light incident direction and have zoom function, and the present embodiment detects light and returns pump light
Specific diameter >=the 20mm of combined beam light.When atom passes through detection cavity, after opening detection light and persistently specifying long-time, photodetection
Systematic survey is currently at the atomicity of F=2 states, is spaced default after-applied time pump light at the first time will be in the original of F=1 states
Son returns pump and arrives F=2 states, and detection light is again turned on after default second time, and photoelectric detecting system measures in current atomic group
Total atom number in F=1 states and F=2 states, obtains the transition probability of atom, as：
P1=1-N2/(N1+N2)。
Further include the polarization direction that optics quarter wave plate is used to adjust Raman light in the present embodiment, optics quarter wave plate is specific
At the top of vacuum chamber, the output end of Raman light.Quarter wave plate specifically uses uniformity good and has graduated wave plate, with convenient
Adjust the polarization direction of raman laser.
The present embodiment controls the sequential of Raman light to control Raman pulse by the way that timing control and data processing system is arranged
With the action time of atomic group, the magnetic field intensity of position is calculated using above-mentioned (2), (3), (4), is participated in without artificial
The automatic measurement for realizing magnetic field in vacuum chamber measures efficiently compared to manual measurement and precision is high.Timing control and data processing
Specifically use can provide multi-channel analog/digital signal and TTL trigger signals to system, and can further be arranged two by control
Or multiple sweep parameters, enabling convenient to realize automatically controlling for entire measurement sequential.
Further include the polarization direction that optics quarter wave plate is used to adjust Raman light in the present embodiment, optics quarter wave plate is specific
At the top of vacuum chamber, the output end of Raman light generation unit.Quarter wave plate specifically uses uniformity good and has graduated wave
Piece, to facilitate the polarization direction of adjustment raman laser.
Above-mentioned only presently preferred embodiments of the present invention, is not intended to limit the present invention in any form.Although of the invention
Disclosed above with preferred embodiment, however, it is not intended to limit the invention.Therefore, every without departing from technical solution of the present invention
Content, technical spirit any simple modifications, equivalents, and modifications made to the above embodiment, should all fall according to the present invention
In the range of technical solution of the present invention protection.
Claims (9)
1. a kind of quick magnetic field measurement method based on Raman spectrum, which is characterized in that step includes：
S1. Raman spectrometry：Prepare cold atom cloud；By cold atom cloud upthrow or free-falling, when atom enters vacuum chamber to be measured
Raman π pulses and atomic interaction are utilized afterwards, and measures the Raman spectrum in vacuum chamber to be measured at different role position, are obtained pair
Answer the Raman modal data of each active position；
S2. Raman spectrum is fitted：Each group Raman modal data is fitted using compound Lapie's function respectively, obtains corresponding to each effect
The resonant frequency of the Raman spectrum of position；
S3. magnetic field intensity calculates：The magnetic field of each target location is calculated using the resonant frequency of the obtained Raman spectrum respectively
Intensity；
In the step S2 Raman modal data described in every group be fitted the specific steps are：
S21. every group of Raman modal data is divided into three sections, extracts atomic transition in each segment data of the Raman modal data respectively
The maximum value of probability and corresponding Raman light frequency；
S22. the maximum value of atomic transition probabilities described in each segment data based on extraction and corresponding Raman light frequency, make
Raman modal data is fitted described in every group of compound Lapie's function pair, obtains three resonant frequencies of current Raman modal data.
2. the quick magnetic field measurement method according to claim 1 based on Raman spectrum, which is characterized in that the step S21
In Raman modal data described in each group is specifically divided into three sections according to wave crest, the compound drawing of the specifically used following formulas of step S22
Raman modal data is fitted described in more every than function pair group；
Wherein, P1For atomic transition probabilities；A-1、A0、A1Respectively fitting Raman spectrum is finally obtained corresponds to mFThe jump of state atom
Move peak heights, mF=-1,0,1, and initial value is respectively to extract corresponding to mFThe maximum value of the atomic transition probabilities of state；ω-1、
ω0、ω1Respectively correspond to mFThe resonant frequency of state atom, and initial value is respectively the maximum value of the atomic transition probabilities extracted
Corresponding Raman light frequency, ΩeffFor effective Rabi frequency of Raman pulse,Respectively Raman light pair
mFThe difference optical frequency shift that state atom generates, δDFor effective Doppler frequency shift, τ is Raman pulse operating time.
3. the quick magnetic field measurement method according to claim 1 or 2 based on Raman spectrum, which is characterized in that the step
S3 the specific steps are：
S31. according to the fitting Raman spectrum under Left-hand circular polarization raman laser, right-hand circular polarization raman laser at target effect site
Three resonant frequencies, calculate separately the difference of first, third resonant frequency in three resonant frequencies, obtain difference in resonance frequencies；
S32. the magnetic field intensity B of Left-hand circular polarization state is calculated according to the difference in resonance frequencies respectivelyIt is left, right-hand circular polarization shape
The magnetic field intensity B of stateIt is right；
S33. according to the magnetic field intensity B of the Left-hand circular polarization stateIt is left, right-hand circular polarization state magnetic field intensity BIt is rightIt is calculated
Absolute magnetic field strengths at target effect site
4. the quick magnetic field measurement method according to claim 1 or 2 based on Raman spectrum, which is characterized in that the step
S1 the specific steps are：
S11. cold atom cloud is prepared；
S12. by the cold atom cloud upthrow of preparation or free-falling；
S13. two beam raman lasers and atomic interaction are utilized after atom enters vacuum chamber to be measured so that atomic group generates drawing
Graceful transition；
S14. the transition probability of Measurement atom；
S15. the relative frequency for scanning two beam raman lasers, repeats step S11~S14, until obtaining current active position
The Raman spectrum at place；
S16. the time of delay Raman π pulses and atom effect, step S11~S15 is repeated, until obtaining vacuum chamber to be measured
Raman spectrum at interior different role position.
5. the quick magnetic field measurement method according to claim 4 based on Raman spectrum, it is characterised in that：The step S11
In specifically in Magneto-Optical Trap, the parameter by adjusting Magneto-Optical Trap prepared on the atomic state in F=2, temperature≤10 μ k cold original
Son group.
6. the quick magnetic field measurement method according to claim 4 based on Raman spectrum, it is characterised in that：The Raman π arteries and veins
Punching is specifically less than the short pulse of 2ms；Frequency sweep stepping when scanning Raman light in the step S14 is less than the frequency domain of Raman pulse
Broadening, swept frequency range when scanning Raman light are more than atom single order Zeeman frequency displacement.
7. according to the quick magnetic field measurement method based on Raman spectrum described in claim 4, which is characterized in that the step S14's
The specific steps are：Detection cavity of the arrangement for Measurement atom state in advance is opened detection light and is continued when atom passes through detection cavity
After specified long-time, the atomicity N for being currently at F=2 states is measured2, it is spaced the original in F=1 states after presetting first time
Son returns pump and arrives F=2 states, and is again turned on detection light after default second time, measures and is in F=1 states and F in current atomic group
The total atom number of=2 states is N1+N2, according to P1=1-N2/(N1+N2) transition probability of atom is calculated.
8. a kind of quick magnetic field measuring device based on Raman spectrum, including：
Raman spectrum measurement module, including vacuum chamber to be measured, be used to prepare and imprison cold atom cloud Magneto-Optical Trap component, for generating
Two beam raman lasers, and frequency to two beam raman lasers and phase controlled raman laser system, be used for Measurement atom
The atomic state detection system of the transition probability of atom in group, and for controlling Magneto-Optical Trap capture, release or upthrow atomic group, drawing
Graceful laser and the time of atomic group effect and the sequential control system of the detection of atom final states；After preparing cold atom cloud, it will make
Standby atomic group upthrow or free-falling in vacuum chamber to be measured using two beam Raman lights and atomic interaction, and are measured and are waited for
The Raman spectrum at different role position in vacuum chamber is surveyed, the multigroup Raman modal data for corresponding to each active position is obtained；
Raman spectrum fitting module is obtained for being fitted respectively using compound Lapie's function according to by each group Raman modal data
The resonant frequency of the Raman spectrum of corresponding each active position；
Magnetic field intensity calculates module, for calculating each target location using the resonant frequency of the obtained Raman spectrum respectively
Magnetic field intensity；
Raman modal data described in every group, which is fitted, in the Raman spectrum fitting module specifically includes：
Every group of Raman modal data is divided into three sections, extracts atomic transition probabilities in each segment data of the Raman modal data respectively
Maximum value and corresponding Raman light frequency；
The maximum value of atomic transition probabilities described in each segment data based on extraction and corresponding Raman light frequency, using multiple
It closes Raman modal data described in every group of Lapie's function pair to be fitted, obtains three resonant frequencies of current Raman modal data.
9. device according to claim 8, which is characterized in that be provided with quantization magnetic field line in the vacuum chamber to be measured
Circle, for generating quantum magnetizing field；The cold atom cloud prepared in the Magneto-Optical Trap component is on the atomic state of F=2, and temperature
≤10μk。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710812881.0A CN107607890B (en) | 2017-09-11 | 2017-09-11 | Raman spectrum-based rapid magnetic field measurement method and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710812881.0A CN107607890B (en) | 2017-09-11 | 2017-09-11 | Raman spectrum-based rapid magnetic field measurement method and device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107607890A CN107607890A (en) | 2018-01-19 |
| CN107607890B true CN107607890B (en) | 2018-10-09 |
Family
ID=61062454
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710812881.0A Active CN107607890B (en) | 2017-09-11 | 2017-09-11 | Raman spectrum-based rapid magnetic field measurement method and device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107607890B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112729355B (en) * | 2020-12-24 | 2023-03-17 | 华中光电技术研究所（中国船舶重工集团公司第七一七研究所） | Method for calibrating Raman light incident angle suitable for atomic interferometer |
| CN112857409B (en) * | 2020-12-31 | 2022-08-09 | 华中光电技术研究所（中国船舶重工集团公司第七一七研究所） | Automatic data acquisition and analysis system of cold atom interferometer |
| CN114441507B (en) * | 2022-04-08 | 2022-09-23 | 港湾之星健康生物(深圳)有限公司 | Quantum magneto-optical sensing method |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7915577B2 (en) * | 2008-05-01 | 2011-03-29 | The United States Of America As Represented By The Secretary Of The Navy | Single-shot spatially-resolved imaging magnetometry using ultracold atoms |
| CN104880614B (en) * | 2015-06-09 | 2017-06-20 | 华南师范大学 | Microwave electric field intensitometer and its measuring method based on cold Rydberg atom interferometer |
| CN105068025B (en) * | 2015-07-16 | 2017-08-11 | 山西大学 | Method and device based on electromagnetic induced transparency effect measurement Weak magentic-field field strength |
| CN105066991B (en) * | 2015-08-07 | 2017-08-25 | 中国船舶重工集团公司第七一七研究所 | Inertia measurement equipment based on cold atom principle of interference |
| CN106842074B (en) * | 2017-03-03 | 2019-07-02 | 中国人民解放军国防科学技术大学 | Three axial vector atom magnetometers and application method based on longitudinal magnetic field modulation |
-
2017
- 2017-09-11 CN CN201710812881.0A patent/CN107607890B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN107607890A (en) | 2018-01-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107607890B (en) | Raman spectrum-based rapid magnetic field measurement method and device | |
| CN107632277B (en) | Automatic magnetic field measuring method and device | |
| CN105049040B (en) | A kind of method that Atomic Clocks Based on Coherent Population Trapping output frequency is corrected using GNSS | |
| CN103823356B (en) | Based on passive-type CPT atomic clock experimental provision and the method for PXI system | |
| CN103855599B (en) | Utilize the method that scanning confocal chamber F-P interferometer realizes laser rrequency-offset-lock | |
| CN109343069A (en) | The photon counting laser radar and its distance measuring method of assembled pulse ranging can be achieved | |
| CN106442378B (en) | The device of spectral absorption accurate testing degree is improved based on Terahertz light comb | |
| CN101847994A (en) | Method and device for implementing Ramsey-CPT atomic frequency standard by microwave periodic On-Off modulation VCSEL | |
| CN105548036A (en) | Self-adaptive double-light-comb spectrum system | |
| CN105700271A (en) | Optical synthesizer tuning using fine and coarse optical frequency combs | |
| CN104953459B (en) | A kind of transmission cavity frequency stabilization system that laser frequency is steady in a long-term and its frequency-stabilizing method | |
| CN113746546A (en) | Optical frequency comb locking method and system based on event timing | |
| CN104483097B (en) | The device and method of measurement gating image intensifier optics gate-width | |
| CN108539571A (en) | A kind of fast automatic mode locking method covering multimode pulse recognition | |
| Hannemann et al. | Frequency metrology on the Mg 3 s 2 S 1→ 3 s 4 p P 1 line for comparison with quasar data | |
| CN107957298A (en) | A kind of laser frequency saltus step measuring device | |
| Meshkov et al. | A new station for optical observation of electron beam parameters at electron storage ring SIBERIA-2 | |
| Brosi | Overview of the micro-bunching instability in electron storage rings and evolving diagnostics | |
| CN106788426A (en) | A kind of CPT atomic frequency standard laser frequency modulation index locking device and method | |
| Schmerge et al. | Photocathode rf gun emittance measurements using variable-length laser pulses | |
| Daigle et al. | Photon counting with an EMCCD | |
| CN205037969U (en) | Programme -controlled reputation spectral detection system gains based on variable OSK radio frequency modulation | |
| Xue et al. | High precision linear frequency modulation ranging system based on semiconductor laser | |
| CN106159668B (en) | A kind of repetition rate locking device and method | |
| CN109781632B (en) | Double-beam pumping detection two-dimensional spectrum measurement system and working method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |