CN114965291A - Measurement of 6 Device and method for total collision cross section of Li cold atoms - Google Patents
Measurement of 6 Device and method for total collision cross section of Li cold atoms Download PDFInfo
- Publication number
- CN114965291A CN114965291A CN202210418391.3A CN202210418391A CN114965291A CN 114965291 A CN114965291 A CN 114965291A CN 202210418391 A CN202210418391 A CN 202210418391A CN 114965291 A CN114965291 A CN 114965291A
- Authority
- CN
- China
- Prior art keywords
- optical trap
- dimensional magneto
- dimensional
- optical
- trap
- 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.)
- Pending
Links
- 238000005259 measurement Methods 0.000 title claims abstract description 28
- 238000000034 method Methods 0.000 title claims abstract description 11
- 238000005086 pumping Methods 0.000 claims abstract description 40
- 108010083687 Ion Pumps Proteins 0.000 claims abstract description 21
- 239000010936 titanium Substances 0.000 claims abstract description 11
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 11
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims abstract description 10
- 238000001816 cooling Methods 0.000 claims description 30
- 230000008878 coupling Effects 0.000 claims description 23
- 238000010168 coupling process Methods 0.000 claims description 23
- 238000005859 coupling reaction Methods 0.000 claims description 23
- 230000003287 optical effect Effects 0.000 claims description 19
- 239000000835 fiber Substances 0.000 claims description 17
- 230000010287 polarization Effects 0.000 claims description 17
- 239000013307 optical fiber Substances 0.000 claims description 12
- 238000010438 heat treatment Methods 0.000 claims description 11
- 238000005516 engineering process Methods 0.000 claims description 5
- 229920006395 saturated elastomer Polymers 0.000 claims description 5
- QJVKUMXDEUEQLH-UHFFFAOYSA-N [B].[Fe].[Nd] Chemical compound [B].[Fe].[Nd] QJVKUMXDEUEQLH-UHFFFAOYSA-N 0.000 claims description 4
- 238000000862 absorption spectrum Methods 0.000 claims description 4
- 239000012535 impurity Substances 0.000 claims description 4
- 229910001172 neodymium magnet Inorganic materials 0.000 claims description 4
- 230000002238 attenuated effect Effects 0.000 claims description 3
- 238000000691 measurement method Methods 0.000 claims description 2
- 230000010355 oscillation Effects 0.000 claims 1
- 239000007789 gas Substances 0.000 description 29
- 238000010521 absorption reaction Methods 0.000 description 5
- 229910052744 lithium Inorganic materials 0.000 description 5
- 239000002245 particle Substances 0.000 description 5
- 230000008859 change Effects 0.000 description 4
- 102000006391 Ion Pumps Human genes 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000002834 transmittance Methods 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000003595 spectral effect Effects 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 101100448366 Arabidopsis thaliana GH3.12 gene Proteins 0.000 description 1
- 101100245381 Caenorhabditis elegans pbs-6 gene Proteins 0.000 description 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- 238000010420 art technique Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005281 excited state Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 230000005283 ground state Effects 0.000 description 1
- 230000003116 impacting effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000000960 laser cooling Methods 0.000 description 1
- 150000002641 lithium Chemical group 0.000 description 1
- 238000010584 magnetic trap Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000000859 sublimation Methods 0.000 description 1
- 230000008022 sublimation Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/21—Polarisation-affecting properties
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L21/00—Vacuum gauges
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/39—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using tunable lasers
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/64—Fluorescence; Phosphorescence
- G01N21/6402—Atomic fluorescence; Laser induced fluorescence
- G01N21/6404—Atomic fluorescence
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R13/00—Arrangements for displaying electric variables or waveforms
- G01R13/02—Arrangements for displaying electric variables or waveforms for displaying measured electric variables in digital form
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/12—Measuring rate of change
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R21/00—Arrangements for measuring electric power or power factor
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/39—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using tunable lasers
- G01N2021/391—Intracavity sample
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2201/00—Features of devices classified in G01N21/00
- G01N2201/06—Illumination; Optics
- G01N2201/061—Sources
- G01N2201/06113—Coherent sources; lasers
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Optics & Photonics (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The application relates to the technical field of precision measurement, in particular to measurement 6 The device comprises a vacuum pumping system, an air inlet system, an ionization vacuum gauge, 6 Li source, two-dimensional magneto-optical trap and three-dimensional magneto-optical trap, wherein: vacuum of air inlet system through pipeline and three-dimensional magneto-optical trapThe chambers are connected; the ionization vacuum gauge is arranged on a pipeline between the air inlet system and the three-dimensional magneto-optical trap; the molecular pump and the dry pump are arranged between the gas cylinder and the fine adjustment valve, and the titanium pump and the first ion pump are arranged on a pipeline between the fine adjustment valve and the three-dimensional magneto-optical trap; the three-dimensional magneto-optical trap is connected with the two-dimensional magneto-optical trap through a pipeline; the second ion pump is arranged on a pipeline between the three-dimensional magneto-optical trap and the two-dimensional magneto-optical trap; 6 the Li source is connected to a two-dimensional magneto-optical trap. According to the method, the absolute number of target cold atoms is not required to be known, only different potential well depths are required to be changed, the loss rate is obtained according to the relation between the background gas pressure and the loss rate, and the accurate measurement of the total collision cross section can be realized.
Description
Technical Field
The application relates to the technical field of precision measurement, in particular to measurement 6 Device and method for total collision cross section of Li cold atoms
Background
Among the collisions of supercooled atoms, the study of the collision cross section of atoms is a popular study subject, the size of the collision cross section of particles reflects the probability of collision of particles, and important information such as the loss rate of captured particles, two-body and multi-body collision parameters, and the depth of potential wells in atomic cooling and BEC experiments can be obtained by studying the collision cross section of particles.
The prior art for measuring collision cross-sections of cold atoms generally uses a highly collimated cross-laser beam, i.e. two perpendicular collimated beams of atoms (or molecules) that cross at a fixed interaction region, and then the cross-section is measured by detecting the atoms scattered from one of these beams at a defined angle relative to the incident beam by means of a particle detector with a slit.
However, the measurement of the total collision cross section is difficult with this prior art technique because the absolute number of cold atoms needs to be determined during the measurement process and the overlap in the atomic beam causes errors.
Disclosure of Invention
The main object of the present application is to provide a measurement 6 Device and method for total collision cross section of Li cold atoms by using cold atoms captured in magneto-optical trap or magnetic trapThe cold atom absolute collision cross section is measured by the loss rate of collision with the background gas, the absolute number of the target cold atoms is not required to be known, and the absolute pressure of the collision gas type and the depth of a potential well are only required to be known, so that the cold atom absolute collision cross section can be accurately measured when colliding with different background gases 6 Total collision cross section of Li cold atoms.
In order to achieve the above object, the present application provides a measurement 6 The device for total collision cross section of Li cold atoms comprises a vacuum pumping system, an air inlet system, an ionization vacuum gauge, 6 Li source, two-dimensional magneto-optical trap and three-dimensional magneto-optical trap, wherein: the air inlet system is connected with the vacuum chamber of the three-dimensional magneto-optical trap through a pipeline and comprises an air bottle and a fine adjustment valve; the ionization vacuum gauge is arranged on a pipeline between the air inlet system and the three-dimensional magneto-optical trap; the vacuum pumping system comprises a molecular pump, a dry pump, a titanium pump, a first ion pump and a second ion pump, wherein the molecular pump and the dry pump are arranged between the gas cylinder and the fine adjustment valve, and the titanium pump and the first ion pump are arranged on a pipeline between the fine adjustment valve and the three-dimensional magneto-optical trap; the three-dimensional magneto-optical trap is connected with the two-dimensional magneto-optical trap through a pipeline; the second ion pump is arranged on a pipeline between the three-dimensional magneto-optical trap and the two-dimensional magneto-optical trap; 6 the Li source is connected to a two-dimensional magneto-optical trap.
And the three-dimensional magneto-optical trap is connected with the oscilloscope sequentially through the band-pass filter, the collimating lens and the photomultiplier.
Furthermore, the device also comprises a differential tube which is arranged between the three-dimensional magneto-optical trap and the two-dimensional magneto-optical trap.
Furthermore, the magnetic field of the three-dimensional magneto-optical trap consists of anti-Helmholtz coils and comprises three groups of polarized laser correlation devices.
Furthermore, each group of polarized laser correlation devices of the three-dimensional magneto-optical trap comprises a fiber coupling head, an 1/2 wave plate, a polarization beam splitter prism, a 1/4 wave plate and a total reflection mirror.
Furthermore, the magnetic field of the two-dimensional magneto-optical trap consists of two groups of neodymium iron boron permanent magnets and comprises two groups of polarized laser correlation devices.
Furthermore, each group of polarized laser correlation devices of the two-dimensional magneto-optical trap comprises a fiber coupling head, a polarization splitting prism, an 1/4 wave plate and a total reflection mirror.
Furthermore, angle valves are arranged between the molecular pump and the gas cylinder and between the molecular pump and the fine adjustment valve.
Further, still include laser optical path system, laser optical path system includes 2D light path part, 3D light path part and locks the light path part, wherein: the 3D light path part can form three-dimensional cooling light and three-dimensional re-pumping light, and two beams of light are coupled and then emitted into the three-dimensional magneto-optical trap through fiber coupling heads in the three groups of polarized laser correlation devices of the three-dimensional magneto-optical trap; the 2D light path part can form push laser, two-dimensional cooling light and two-dimensional re-pumping light, the push laser is directly emitted into the two-dimensional magneto-optical trap along the horizontal direction through the optical fiber coupling head and the 1/2 wave plate, and the two-dimensional cooling light and the two-dimensional re-pumping light are coupled and then emitted into the two-dimensional magneto-optical trap through the optical fiber coupling heads in the two groups of polarization laser correlation devices of the two-dimensional magneto-optical trap; the locking optical path part is used for locking the laser based on a saturated absorption spectrum technology.
In addition, the application also provides an application measurement 6 The method for the total collision of Li cold atoms on a cross section device comprises the following steps: step 1, opening a vacuum pumping system to pump the vacuum chamber to a vacuum degree of 1 × 10 -8 Pa, then heating 6 Li source to 513K, reacting 6 Li atoms are ejected out along the vertical direction and enter the two-dimensional magneto-optical trap; step 2, opening a laser light path system to form a 2D light path and a 3D light path, and injecting the 2D light path into the two-dimensional magneto-optical trap and injecting the 3D light path into the three-dimensional magneto-optical trap; step 3, 6 The Li atoms are reduced in atom speed and confined above the heating device in a two-dimensional cooling and confining mode in the two-dimensional magneto-optical trap, and the cold atoms in the two-dimensional magneto-optical trap can be pushed to the three-dimensional magneto-optical trap through the differential tube by the pushing laser in the horizontal direction to be loaded; step 4, opening an angle valve, pumping the pipeline through a molecular pump and a dry pump, closing the angle valve after the impurity gas is pumped, conveying the gas to a vacuum chamber in the three-dimensional magneto-optical trap, and controlling the flow of the gas entering the vacuum chamber through adjusting a fine adjustment valve; and 5, observing whether the vacuum degree is stable or not by using an ionization vacuum gauge, observing the fluorescence power of the cold atoms by using an oscilloscope, and considering that the fluorescence power is stableClosing the two-dimensional magneto-optical trap and pushing laser after cold atoms are loaded; step 6, at the moment, the cold atoms in the three-dimensional magneto-optical trap collide with introduced gas molecules, the number of the cold atoms is attenuated, data is recorded, the loss rate of the cold atoms can be obtained according to a formula, the vacuum degree is changed for many times, the corresponding loss rate is measured, and the loss rate coefficient of the depth of the potential well can be obtained through fitting according to the formula; and 7, adjusting a laser light path system, changing the frequency detuning and the light power of incident cooling light, so that the trap depth of the three-dimensional magneto-optical trap can be adjusted, gradually making the trap shallow, repeating the step 6 for changing the vacuum degree and measuring the corresponding loss rate every time the trap is adjusted, fitting to obtain the loss rate coefficient when the depth of the potential trap is 0, and finally gradually extrapolating to obtain the loss rate coefficient when the depth of the potential trap is 0, namely the total collision cross section.
The invention provides a measurement 6 The device and the method for the total collision cross section of the Li cold atoms have the following beneficial effects:
this application utilizes laser cooling 6 The Li atoms are used for measuring the total collision cross section, the mode of transferring the three-dimensional magneto-optical trap by the two-dimensional magneto-optical trap is adopted, the collision between the hot atoms and the cold atoms in the cavity is avoided, the atom loss is reduced, the influence of the heating of the conventional Zeeman reducer during working on the background gas temperature is improved, the capture of large atom number is realized in the three-dimensional magneto-optical trap, the measurement uncertainty is reduced, the absolute number of target cold atoms is not needed to be known, only the depths of different potential wells are needed to be changed, and the loss rate is obtained according to the relation between the pressure of the background gas and the loss rate, so that the accurate measurement of the total collision cross section can be realized.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, serve to provide a further understanding of the application and to enable other features, objects, and advantages of the application to be more apparent. The drawings and their description illustrate the embodiments of the invention and do not limit it. In the drawings:
FIG. 1 is a measurement provided according to an embodiment of the present application 6 A structural diagram of a device of a total collision cross section of Li cold atoms;
FIG. 2Is a measurement provided according to an embodiment of the present application 6 Laser light path diagram of the device of total collision cross section of Li cold atoms;
FIG. 3 is a measurement provided according to an embodiment of the present application 6 A parameter design drawing of a two-dimensional magneto-optical trap, a three-dimensional magneto-optical trap and a push laser of the device of the total collision cross section of the Li cold atoms;
in the figure: 1-ionization vacuum gauge, 2-angle valve, 3-molecular pump, 4-dry pump, 5-fine adjustment valve, 6-gas cylinder, 7-titanium pump, 8-first ion pump, 9-second ion pump, 10-band-pass filter, 11-collimating lens, 12-photomultiplier, 13-differential tube, 14-oscilloscope and 15- 6 The device comprises a Li source, a 16-laser, a 17-lithium atom vapor pool, an FC-fiber coupling head, an M-total reflection mirror, a QWP-1/4 wave plate, an HWP-1/2 wave plate, a PBS-deflection beam splitter prism, a TA-laser amplifier, an ISO-optical isolator, a CL-cylindrical mirror, an AMO-acousto-optic modulator, a BS-beam splitter prism, a PD-photodetector, an Iris-diaphragm and a Glass-high-transmittance low-reflectance mirror.
Detailed Description
In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only partial embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
As shown in FIG. 1, the present application provides a measurement 6 The device for the total collision cross section of the Li cold atoms comprises a vacuum pumping system, an air inlet system, an ionization vacuum gauge 1, 6 Li source 15, two-dimensional magneto-optical trap and three-dimensional magneto-optical trap, wherein: the air inlet system is connected with a vacuum chamber of the three-dimensional magneto-optical trap through a pipeline and comprises an air bottle 6 and a fine adjustment valve 5; the ionization vacuum gauge 1 is arranged on a pipeline between the air inlet system and the three-dimensional magneto-optical trap; the vacuum pumping system comprises a molecular pump 3, a dry pump 4, a titanium pump 7, a first ion pump 8 and a second ion pump 9, wherein the molecular pump 3 and the dry pump 4 are arranged between a gas cylinder 6 and a fine adjustment valve 5, and the titanium pump7 and a first ion pump 8 are arranged on a pipeline between the fine adjustment valve 5 and the three-dimensional magneto-optical trap; the three-dimensional magneto-optical trap is connected with the two-dimensional magneto-optical trap through a pipeline; the second ion pump 9 is arranged on a pipeline between the three-dimensional magneto-optical trap and the two-dimensional magneto-optical trap; 6 the Li source 15 is connected to a two-dimensional magneto-optical trap.
In particular, the measurements provided in the examples of the present application 6 The device for the total collision cross section of Li cold atoms firstly uses a vacuum pumping system to pump the environment vacuum and then pumps the environment vacuum 6 Heating the Li source 15 to make 6 Li atoms are ejected in the vertical direction and enter a two-dimensional magneto-optical trap, the atom speed is reduced and trapped above a heating device in a two-dimensional cooling trapping way, cold atoms in the two-dimensional magneto-optical trap can be pushed to the area of the three-dimensional magneto-optical trap through a differential tube 13 by pushing laser in the horizontal direction, a photomultiplier 12 is used for collecting fluorescence signals of the cold atoms in the three-dimensional magneto-optical trap and converting the fluorescence signals into electric signals to be displayed on an oscilloscope 14 for showing the change of the cold atoms, when the oscilloscope 14 shows that the cold atoms are loaded and tend to be unchanged, the laser of the two-dimensional magneto-optical trap, the pushing laser and the laser of the three-dimensional magneto-optical trap are closed through time sequence control, the magnetic field gradient of the three-dimensional magneto-optical trap is increased, the magneto-optical trap is rapidly changed into a magnetic trap, the cooled atoms are trapped, the trapped cold atoms collide with background gas introduced by a fine adjustment valve 5 to cause the loss of the number, and simultaneously a vacuum pumping system and an air inlet system are matched to maintain constant pressure, the loss rate coefficient under a certain fixed trap depth is obtained through the fitting of the measured relation between the loss rate and the pressure, then the collision loss section can be extracted, the trap depth is changed through changing the cooling laser intensity and frequency detuning of the three-dimensional magneto-optical trap, the loss sections under different trap depths can be obtained, and the total collision section can be obtained through extrapolating the loss sections until the depth of the potential well is zero. In the embodiment of the application, the vacuum pumping system adopts the pumping unit of two groups of sputtering ion pumps and titanium sublimation pumps to pump air, the ion pumps are mainly used for maintaining vacuum, when the ion pumps with too many molecules can not be maintained, the titanium pump 7 is opened to maintain, so that the vacuum degree of the system can be improved by one to two orders of magnitude, the second ion pump 9 mainly performs low-vacuum pumping between the two-dimensional magneto-optical trap and the three-dimensional magneto-optical trap, and the first ion pump 8 and the titanium pump 8 perform low-vacuum pumpingThe pump 7 is mainly used for high vacuum pumping between the air inlet system and the three-dimensional magneto-optical trap, the molecular pump 3 and the dry pump 4 are mainly used for pumping impurity gas between the fine adjustment valve 5 and the angle valve 2, and the minimum pressure of the vacuum chamber is 1 multiplied by 10 by adopting the vacuum pumping system with the design -8 Pa. The gas cylinder 6 is mainly used for providing background gas for collision, and an introduced gas source can be generated 10 in the vacuum chamber under the regulation of the fine adjustment valve 5 -8 -10 -6 Pressure of variation in the Pa range. The ionization vacuum gauge 1 is connected with the three-dimensional magneto-optical trap and is mainly used for measuring the vacuum degree of the main vacuum chamber, and the vacuum degree in the vacuum chamber can be adjusted at any time according to the reading of the ionization vacuum gauge 1. 6 2g of metallic lithium is loaded in the Li source 15 at a time, and 513K can be continuously generated after the interior of the Li source is heated step by step 6 And Li atom vapor. After heating 6 The Li atomic vapor firstly reduces the speed of a part of atoms to dozens of m/s through the two-dimensional magneto-optical trap, and after a beam of pushing laser is injected in the horizontal direction, cold atoms are pushed to the three-dimensional magneto-optical trap area along the horizontal direction aligned with the axes of the two-dimensional magneto-optical trap and the three-dimensional magneto-optical trap, and the speed can be reduced to a few m/s.
Further, the device also comprises an oscilloscope 14, and the three-dimensional magneto-optical trap is connected with the oscilloscope 14 through the band-pass filter 10, the collimating lens 11 and the photomultiplier 12 in sequence. The photomultiplier 12 is mainly used for collecting fluorescent signals of cold atoms in the three-dimensional magneto-optical trap and converting the fluorescent signals into electric signals to be displayed on the oscilloscope 14, atomic number changes of the cold atoms can be observed on the oscilloscope 14, voltage changes of the photomultiplier 12 are used for representing atomic number changes, loss rates of the cold atoms can be obtained through fitting, the band-pass filter 10 is mainly used for filtering stray light of other wave bands, and the collimating lens 11 is mainly used for collimating and converging light beams.
Further, a differential tube 13 is also included, and the differential tube 13 is arranged between the three-dimensional magneto-optical trap and the two-dimensional magneto-optical trap. The differential tube 13 is mainly used for maintaining pressure difference, can maintain pressure difference of more than two orders of magnitude, is arranged between the three-dimensional magneto-optical trap and the two-dimensional magneto-optical trap, and can inhibit influence of background gas pressure increase caused by atom heating on the three-dimensional magneto-optical trap.
Furthermore, the magnetic field of the three-dimensional magneto-optical trap consists of anti-Helmholtz coils and comprises three groups of polarized laser correlation devices. The three-dimensional magneto-optical trap magnetic field is composed of anti-Helmholtz coils, the optical field is composed of six beams of cross-correlation reverse circular polarized lasers, and each beam of laser comprises three-dimensional cooling light and three-dimensional re-pumping light which are mixed according to a certain intensity proportion.
Furthermore, each group of polarized laser correlation devices of the three-dimensional magneto-optical trap comprises a fiber coupling head FC, an 1/2 wave plate HWP, a polarization beam splitter prism PBS, a 1/4 wave plate QWP and a total reflection mirror M. The fiber coupling head FC can change the size, shape and other properties of laser spots entering the fiber, and the curve at the back represents the fiber connected with the fiber, and mainly shapes laser beams and then leads the laser beams into or out of the fiber; 1/2 the HWP is mainly used to rotate the polarized light, when the incident light is left (right) polarized light, the emergent light will be right (left) polarized light; 1/4 wave plate QWP is mainly used to change the polarization state of polarized light, when the incident light is linear polarized light, the transmitted light will become circular polarized light, when the incident light is circular polarized light, the emergent light will become linear polarized light; the polarizing beam splitter PBS is mainly used for separating horizontal polarization and vertical polarization of light; the total reflection mirror M mainly reflects the incident laser light out.
Furthermore, the magnetic field of the two-dimensional magneto-optical trap consists of two groups of neodymium iron boron permanent magnets and comprises two groups of polarized laser correlation devices. The magnetic field of the two-dimensional magneto-optical trap is generated by two groups of neodymium iron boron permanent magnets, the optical field is composed of four beams of crossed and opposite reverse circular polarized lasers, each beam of laser comprises two-dimensional cooling light and two-dimensional re-pumping light which are mixed according to a certain intensity proportion, and the push laser is emitted into the three-dimensional magneto-optical trap along the horizontal direction of the two-dimensional magneto-optical trap.
Furthermore, each group of polarized laser correlation devices of the two-dimensional magneto-optical trap comprises an optical fiber coupling head FC, a polarization beam splitter PBS, 1/4 wave plates QWP and a total reflection mirror M.
Furthermore, angle valves 2 are arranged between the molecular pump 3 and the gas cylinder 6 and between the fine adjustment valve 5. The angle valve 2 is mainly used for controlling the on-off of the air suction of the molecular pump 3 and the gas delivery of the gas bottle 6.
Further, still include laser optical path system, laser optical path system includes 2D light path part, 3D light path part and locks the light path part, wherein: the 3D light path part can form three-dimensional cooling light and three-dimensional re-pumping light, and two beams of light are coupled and then injected into the three-dimensional magneto-optical trap through fiber coupling heads FC in the three groups of polarized laser correlation devices of the three-dimensional magneto-optical trap; the 2D light path part can form push laser, two-dimensional cooling light and two-dimensional re-pumping light, the push laser is directly injected into the two-dimensional magneto-optical trap along the horizontal direction through the fiber coupling heads FC and the 1/2 wave plate HWP, and the two-dimensional cooling light and the two-dimensional re-pumping light are coupled and then injected into the two-dimensional magneto-optical trap through the fiber coupling heads FC in the two groups of polarized laser correlation devices of the two-dimensional magneto-optical trap; the locking optical path part is used for locking the laser based on a saturated absorption spectrum technology.
Specifically, the laser optical path system is shown in fig. 2, the laser parameters are shown in fig. 3, the laser 16 directly outputs a part of laser light, and the part of laser light passes through the acousto-optic modulators AOM3 and AOM4 to be used as cooling light and re-pumping light of the three-dimensional magneto-optical trap respectively, wherein the frequency of the cooling light is relative to that of the re-pumping light 6 D of Li 2 Line |2 2 S 1/2 ，F＝3/2>→|2 2 P 3/2 ，F′＝5/2>Red down detuning delta 3Dc Frequency of re-pumped light relative to 6 D of Li 2 Line |2 2 S 1/2 ，F＝1/2>→|2 2 P 3/2 ，F′＝5/2>Red down detuning delta 3Dr Two beams of laser are output by the coupling heads FC4 and FC5 and then coupled into a single-mode polarization-maintaining optical fiber, are connected with the optical fiber coupling heads FC in the three groups of polarization laser correlation devices in the three-dimensional magneto-optical trap after being split by the optical fiber, and form three pairs of mutually-perpendicular and cross-correlation reverse circular polarization cooling light and re-pumping light in the three-dimensional magneto-optical trap. And the other part of the light output by the laser 16 is amplified by the laser amplifier TA, and then is used as cooling light and re-pumping light of a two-dimensional magneto-optical trap after being amplified by the power of the laser amplifier TA and also passing through two acousto-optic modulators AOM1 and AOM2, wherein the cooling light is locked at |2 2 S 1/2 ，F＝3/2>→|2 2 P 3/2 ，F′＝5/2>Red down detuning delta 2Dc And the re-pumping light is locked at |2 2 S 1/2 ，F＝1/2>→|2 2 P 3/2 ，F′＝5/2>Red down detuning delta 2Dr Two beams of lightThe laser is coupled into a single-mode polarization-maintaining fiber after being output by the coupling heads FC2 and FC3, is connected with the fiber coupling heads FC in the two groups of polarization laser correlation devices of the two-dimensional magneto-optical trap after being split by the fiber, and forms two pairs of cross correlation reverse circular polarization cooling light and re-pumping light in the two-dimensional magneto-optical trap. In addition, a part of two-dimensional cooling light is output as push laser through a coupling head FC1 through a polarization beam splitter PBS6, then is connected with a horizontal optical fiber coupling head FC in the two-dimensional magneto-optical trap through an optical fiber, and is directly emitted into the two-dimensional magneto-optical trap along the horizontal direction. It is desirable that the frequency of the laser 16 be locked at all times while the laser is cooling the atoms 6 D of Li atom 2 A locked light path part is designed near a transition line based on the saturated absorption spectrum technology, laser emitted from a laser 16 is split by PBS3 and then passes through a high-transmittance low-reflectance Glass, a principle that the front surface and the rear surface of a lens have reflection effects is utilized, a laser beam is divided into two beams of weak emission light with equal light power and one beam of transmission light with stronger power, the two beams of reflection light are emitted into a lithium atom steam pool 17 in parallel, the transmitted strong light is emitted into the steam pool from the opposite direction and is shot against one beam of reflection light, due to the stronger power of the transmission light, a large number of ground state atoms are pumped to an excited state near an atomic resonance line, so that the number of atoms interacting with the weak light is reduced, the absorption proportion of the weak light is reduced, a convex small peak appears near a resonance point of the weak light, and is subtracted from an absorption signal of weak reference light, an atomic absorption spectral line can be obtained, and the laser 16 is locked on the small peak of the atomic absorption spectral line, finally the laser 16 is locked. The laser optical path diagram in the embodiment of the application is mainly used for injecting push laser, two-dimensional cooling light and two-dimensional re-pumping light into the two-dimensional magneto-optical trap, and injecting three-dimensional cooling light and three-dimensional re-pumping light into the three-dimensional magneto-optical trap, and the positions and the number of optical components such as 1/2 wave plate HWP, polarization beam splitter PBS, total reflection mirror M, laser amplifier TA, optical isolator ISO, cylindrical mirror CL, acousto-optic modulator AMO, 1/4 wave plate QWP, beam splitter BS, photodetector PD, diaphragm Iris, high-transmittance low-reflection mirror Glass in fig. 2 are not specifically limited.
In addition, the application also provides an application measurement 6 Total collision of Li cold atomsA method of impacting a cross-sectional device comprising the steps of:
and 6, at the moment, the cold atoms in the three-dimensional magneto-optical trap collide with introduced gas molecules, the number of the cold atoms is attenuated, data is recorded, and P can be extracted according to the formula (1) 1 Loss rate of cold atoms gamma 0 ，
In the formula (1), gamma 0 For trapping cold source and background gasLoss rate of molecular collisions, beta is the density-dependent loss rate between trapped atoms, N t The change of the number of atoms is measured by using fluorescence scattered by trapped atoms and can be drawn as a function of time, and the loss rate gamma under different vacuum degrees can be extracted from the attenuation curve 0 Changing the vacuum degree for multiple times, measuring the corresponding loss rate, and fitting according to a formula (2) to obtain a loss rate coefficient of the depth U of the potential well;
Γ 0 ＝n＜σ loss (U)v bg > (2)
in the formula (2), n is the density of the background gas, and n is p/k B T is obtained, loss rate coefficient
Wherein the content of the first and second substances,
average velocity of background gas, m bg Is the background gas molecular mass, T is the background temperature;
and 7, adjusting a laser light path system, changing the frequency detuning and the light power of incident cooling light, so that the trap depth of the three-dimensional magneto-optical trap can be adjusted, gradually making the trap shallow, repeating the step 6 for changing the vacuum degree and measuring the corresponding loss rate every time the trap is adjusted, fitting to obtain the loss rate coefficient when the depth of the potential trap is 0, and finally gradually extrapolating to obtain the loss rate coefficient when the depth of the potential trap is 0, namely the total collision cross section.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims (10)
1. Measurement method 6 The device for the total collision cross section of the Li cold atoms is characterized by comprising a vacuum pumping system, an air inlet system, an ionization vacuum gauge, 6 Li source, two-dimensional magneto-optical trap and three-dimensional magnetAn optical trap, wherein:
the air inlet system is connected with the vacuum chamber of the three-dimensional magneto-optical trap through a pipeline and comprises an air bottle and a fine adjustment valve;
the ionization vacuum gauge is arranged on a pipeline between the air inlet system and the three-dimensional magneto-optical trap;
the vacuum pumping system comprises a molecular pump, a dry pump, a titanium pump, a first ion pump and a second ion pump, wherein the molecular pump and the dry pump are arranged between the gas cylinder and the fine adjustment valve, and the titanium pump and the first ion pump are arranged on a pipeline between the fine adjustment valve and the three-dimensional magneto-optical trap;
the three-dimensional magneto-optical trap is connected with the two-dimensional magneto-optical trap through a pipeline;
the second ion pump is arranged on a pipeline between the three-dimensional magneto-optical trap and the two-dimensional magneto-optical trap;
the above-mentioned 6 A Li source is connected to the two-dimensional magneto-optical trap.
2. Measurement according to claim 1 6 The device for the total collision cross section of the Li cold atoms is characterized by further comprising an oscilloscope, wherein the three-dimensional magneto-optical trap is connected with the oscilloscope sequentially through a band-pass filter, a collimating lens and a photomultiplier.
3. The method of claim 1 6 The device for the total collision cross section of the Li cold atoms is characterized by further comprising a differential tube, wherein the differential tube is arranged between the three-dimensional magneto-optical trap and the two-dimensional magneto-optical trap.
4. Measurement according to claim 1 6 The device for the total collision cross section of the Li cold atoms is characterized in that a magnetic field of the three-dimensional magneto-optical trap consists of anti-Helmholtz coils and comprises three groups of polarized laser correlation devices.
5. The measurement of claim 4 6 The device for the total collision cross section of Li cold atoms is characterized in that each group of three-dimensional magneto-optical traps is biasedThe laser beam oscillation correlation device comprises an optical fiber coupling head, an 1/2 wave plate, a polarization beam splitter prism, a 1/4 wave plate and a total reflection mirror.
6. Measurement according to claim 1 6 The device for the total collision cross section of the Li cold atoms is characterized in that a magnetic field of the two-dimensional magneto-optical trap consists of two groups of neodymium iron boron permanent magnets and comprises two groups of polarized laser correlation devices.
7. Measurement according to claim 6 6 The device for the total collision cross section of the Li cold atoms is characterized in that each group of polarized laser correlation devices of the two-dimensional magneto-optical trap comprises an optical fiber coupling head, a polarization beam splitter prism, an 1/4 wave plate and a total reflection mirror.
8. Measurement according to claim 1 6 The device for the total collision cross section of the Li cold atoms is characterized in that angle valves are arranged between the molecular pump and the gas cylinder and between the fine adjustment valves.
9. The measurement of claim 4 or claim 7 6 The device of the total collision cross section of the Li cold atoms is characterized by further comprising a laser optical path system, wherein the laser optical path system comprises a 2D optical path part, a 3D optical path part and a locking optical path part, and the device comprises:
the 3D light path part can form three-dimensional cooling light and three-dimensional re-pumping light, and two beams of light are coupled and then emitted into the three-dimensional magneto-optical trap through fiber coupling heads in the three groups of polarized laser correlation devices of the three-dimensional magneto-optical trap;
the 2D light path part can form push laser, two-dimensional cooling light and two-dimensional re-pumping light, the push laser is directly injected into the two-dimensional magneto-optical trap along the horizontal direction through an optical fiber coupling head and an 1/2 wave plate, and the two-dimensional cooling light and the two-dimensional re-pumping light are injected into the two-dimensional magneto-optical trap through optical fiber coupling heads in two groups of polarization laser correlation devices of the two-dimensional magneto-optical trap after being coupled;
the locking optical path part locks the laser based on a saturated absorption spectrum technology.
10. Use of a measurement according to any of claims 1-9 6 The method for the total collision of Li cold atoms on the cross section device is characterized by comprising the following steps of:
step 1, opening a vacuum pumping system to pump the vacuum chamber to a vacuum degree of 1 × 10 -8 Pa, then heating 6 Li source to 513K, reacting 6 Li atoms are ejected out along the vertical direction and enter the two-dimensional magneto-optical trap;
step 2, opening a laser light path system to form a 2D light path and a 3D light path, and injecting the 2D light path into the two-dimensional magneto-optical trap and injecting the 3D light path into the three-dimensional magneto-optical trap;
step 3, 6 The Li atoms are reduced in atom speed and confined above the heating device in a two-dimensional cooling and confining mode in the two-dimensional magneto-optical trap, and the cold atoms in the two-dimensional magneto-optical trap can be pushed to the three-dimensional magneto-optical trap through the differential tube by the pushing laser in the horizontal direction to be loaded;
step 4, opening an angle valve, pumping the pipeline through a molecular pump and a dry pump, closing the angle valve after the impurity gas is pumped, conveying the gas to a vacuum chamber in the three-dimensional magneto-optical trap, and controlling the flow of the gas entering the vacuum chamber through adjusting a fine adjustment valve;
step 5, observing whether the vacuum degree is stable through an ionization vacuum gauge, observing the fluorescence power of the cold atoms through an oscilloscope, and closing the two-dimensional magneto-optical trap and pushing laser when the fluorescence power is stable and the cold atoms are considered to be completely loaded;
step 6, at the moment, cold atoms in the three-dimensional magneto-optical trap collide with introduced gas molecules, the number of the cold atoms is attenuated, data is recorded, the loss rate of the cold atoms can be obtained according to a formula, the vacuum degree is changed for multiple times, the corresponding loss rate is measured, and the loss rate coefficient of the depth of the potential well can be obtained through fitting according to the formula;
and 7, adjusting a laser light path system, changing the frequency detuning and the light power of incident cooling light, so that the trap depth of the three-dimensional magneto-optical trap can be adjusted, gradually making the trap shallow, repeating the step 6 for changing the vacuum degree and measuring the corresponding loss rate every time the trap is adjusted, fitting to obtain the loss rate coefficient when the depth of the potential trap is 0, and finally gradually extrapolating to obtain the loss rate coefficient when the depth of the potential trap is 0, namely the total collision cross section.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210418391.3A CN114965291A (en) | 2022-04-20 | 2022-04-20 | Measurement of 6 Device and method for total collision cross section of Li cold atoms |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210418391.3A CN114965291A (en) | 2022-04-20 | 2022-04-20 | Measurement of 6 Device and method for total collision cross section of Li cold atoms |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114965291A true CN114965291A (en) | 2022-08-30 |
Family
ID=82977721
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210418391.3A Pending CN114965291A (en) | 2022-04-20 | 2022-04-20 | Measurement of 6 Device and method for total collision cross section of Li cold atoms |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114965291A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115479695A (en) * | 2022-09-21 | 2022-12-16 | 中国科学院上海光学精密机械研究所 | Cold atom velocity marking and filtering method |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109557061A (en) * | 2018-12-08 | 2019-04-02 | 山西大学 | A kind of method and device measuring molecular constant |
| CN110473649A (en) * | 2019-07-12 | 2019-11-19 | 山西医科大学 | A kind of asymmetric two-dimensional magneto-optical trap method and apparatus preparing super long type Cold atomic cloud |
| US20200025639A1 (en) * | 2018-07-23 | 2020-01-23 | The University Of British Columbia | Quantum pressure standard and methods for determining and using same |
| US20200161446A1 (en) * | 2018-11-20 | 2020-05-21 | ColdQuanta, Inc. | Quantum tunneling matter-wave transistor system |
| CN111199099A (en) * | 2019-12-26 | 2020-05-26 | 兰州空间技术物理研究所 | Method for evaluating operation life of ion thruster based on grid corrosion |
| CN112185604A (en) * | 2020-09-10 | 2021-01-05 | 华南师范大学 | Method for generating bicolor magneto-optical trap applied to ultra-cold ytterbium atomic system |
| CN112485214A (en) * | 2020-12-14 | 2021-03-12 | 核工业理化工程研究院 | Device and method for improving laser absorption spectrum measurement sensitivity |
| CN113740786A (en) * | 2021-09-01 | 2021-12-03 | 西安交通大学 | Method for measuring alkali metal atom density of single-beam SERF atomic magnetometer |
-
2022
- 2022-04-20 CN CN202210418391.3A patent/CN114965291A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20200025639A1 (en) * | 2018-07-23 | 2020-01-23 | The University Of British Columbia | Quantum pressure standard and methods for determining and using same |
| US20200161446A1 (en) * | 2018-11-20 | 2020-05-21 | ColdQuanta, Inc. | Quantum tunneling matter-wave transistor system |
| CN109557061A (en) * | 2018-12-08 | 2019-04-02 | 山西大学 | A kind of method and device measuring molecular constant |
| CN110473649A (en) * | 2019-07-12 | 2019-11-19 | 山西医科大学 | A kind of asymmetric two-dimensional magneto-optical trap method and apparatus preparing super long type Cold atomic cloud |
| CN111199099A (en) * | 2019-12-26 | 2020-05-26 | 兰州空间技术物理研究所 | Method for evaluating operation life of ion thruster based on grid corrosion |
| CN112185604A (en) * | 2020-09-10 | 2021-01-05 | 华南师范大学 | Method for generating bicolor magneto-optical trap applied to ultra-cold ytterbium atomic system |
| CN112485214A (en) * | 2020-12-14 | 2021-03-12 | 核工业理化工程研究院 | Device and method for improving laser absorption spectrum measurement sensitivity |
| CN113740786A (en) * | 2021-09-01 | 2021-12-03 | 西安交通大学 | Method for measuring alkali metal atom density of single-beam SERF atomic magnetometer |
Non-Patent Citations (3)
| Title |
|---|
| 张苏钊 等: "基于冷原子的超高/极高真空测量机理研究进展", 《真空科学与技术学报》, vol. 41, no. 5, 31 May 2021 (2021-05-31), pages 391 - 402 * |
| 张苏钊 等: "基于磁光阱中6Li 冷原子的真空度测量研究", 《物理学报》, 9 February 2022 (2022-02-09), pages 1 - 20 * |
| 张苏钊 等: "基于磁光阱中6Li 冷原子的真空度测量研究", 《物理学报》, pages 1 - 20 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115479695A (en) * | 2022-09-21 | 2022-12-16 | 中国科学院上海光学精密机械研究所 | Cold atom velocity marking and filtering method |
| CN115479695B (en) * | 2022-09-21 | 2024-04-12 | 中国科学院上海光学精密机械研究所 | Cold atomic speed marking and filtering method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Chaudhuri et al. | Realization of an intense cold Rb atomic beam based on a two-dimensional magneto-optical trap: Experiments and comparison with simulations | |
| Schoser et al. | Intense source of cold Rb atoms from a pure two-dimensional magneto-optical trap | |
| Haubrich et al. | Observation of individual neutral atoms in magnetic and magneto-optical traps | |
| Öttl et al. | Correlations and counting statistics of an atom laser | |
| CN102519928B (en) | Detection method capable of realizing direct acquirement of image of single atom | |
| CN114965291A (en) | Measurement of 6 Device and method for total collision cross section of Li cold atoms | |
| Basov et al. | Influence of certain radiation parameters on wavefront reversal of a pump wave in a Brillouin mirror | |
| Panda et al. | Stimulated Raman adiabatic passage preparation of a coherent superposition of ThO H 3 Δ 1 states for an improved electron electric-dipole-moment measurement | |
| Schneider et al. | Ion storage technique for very long living states: The decay rate of the 5 D 3/2 state of Ba II | |
| Lunden et al. | Enhancing the capture velocity of a Dy magneto-optical trap with two-stage slowing | |
| Mocek et al. | Dramatic enhancement of xuv laser output using a multimode gas-filled capillary waveguide | |
| Schmidt et al. | Continuous loading of cold atoms into a Ioffe–Pritchard magnetic trap | |
| Smeets et al. | Instantaneous laser Doppler velocimeter using a fast wavelength tracking Michelson interferometer | |
| Lee et al. | Single-photon superradiant beating from a Doppler-broadened ladder-type atomic ensemble | |
| Biloiu et al. | One-and two-dimensional laser induced fluorescence at oblique incidence | |
| CN110426653B (en) | Method for measuring optical pumping rate | |
| Balik et al. | Optical pumping dynamics and near-resonance light scattering in an ultracold sample of R 87 b atoms | |
| Dos Santos et al. | Efficient magneto-optical trapping of a metastable helium gas | |
| Bouchiat et al. | High precision balanced mode polarimetry with a pulsed laser beam | |
| Greiner et al. | Loading chromium atoms in a magnetic guide | |
| Wickham et al. | Barium ion beam probe for magnetic field, diamagnetism, and space potential measurement in plasmas | |
| Granitza et al. | Simple and efficient method of spin‐polarizing a metastable helium beam by diode laser optical pumping | |
| CN111721410B (en) | System and method for moving single atom position | |
| Ringena | Demonstration of a Dual Atom Trap Trace Analysis Setup for 39Ar and 85Kr | |
| Megyeri | Cold atom ring laser |
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 |