125 results about "Magneto-optical trap" patented technology

A system and method are disclosed for producing a source of ions, and particularly, a focused ion beam. The system and method use a magneto-optical trap (MOT) to produce a population of neutral atoms. A laser is then utilized to ionize atoms and produce a population of ions. An extraction element is then used to transfer the ions so that they can be used in a wide array of applications.

A light-pulse atomic interferometry (LPAI) apparatus is provided. The LPAI apparatus comprises a vessel, two sets of magnetic coils configured to magnetically confine an atomic vapor in two respective magneto-optical traps (MOTs) within the vessel when activated, and an optical system configured to irradiate the atomic vapor within the vessel with laser radiation that, when suitably tuned, can launch atoms previously confined in each of the MOTs toward the other MOT. In embodiments, the magnetic coils are configured to produce a magnetic field that is non-zero at the midpoint between the traps. In embodiments, the time-of-flight of the launched atoms from one MOT to the other is 12 ms or less. In embodiments, the MOTs are situated approximately 36 mm apart. In embodiments, the apparatus is configured to activate the magnetic coils according to a particular temporal magnetic field gradient profile.

The invention discloses a foldable dual-beam magnetic light trap system which is mainly suitable for generating cold atoms in laser cooling. Three pairs of laser with opposite polarization and opposite travelling are formed in a vacuum chamber through reflecting incoming laser many times, and a magnetic light trap is formed under the mutual action of a magnetic field generated by an opposite Helmholtz coil. The foldable dual-beam magnetic light trap system is characterized in that multiple reflections are utilized, and laser energy is repeatedly utilized, thereby obtaining the cold atoms. Theinvention has the advantages of simple structure, easy power balance, stable atomicgroup, low input power of laser and easy adjustment, thereby providing a better cold atom resource for cold atom frequency scale, precise measurement and laser cooling physical test.

The invention discloses a two-dimensional magnetic optical trap system and a narrow line width single photon source preparing method thereof. The system comprises two pairs of reversed Helmholtz coils, a quartz vacuum cavity, an ion pump, a current feed through part with alkali metal releasing agent, a vacuum valve, a six-way connector, a first glass window, a second glass window and a first semiconductor laser. Six openings of the six-way connector are respectively connected with the quartz vacuum cavity, the ion pump, the current feed through part, the vacuum valve, the first glass window and the second glass window. The two pairs of reversed Helmholtz coils are respectively arranged in a horizontal-symmetrical mode and in a vertical-symmetrical mode. According to the method, the two-dimensional magnetic optical trap system obtains a long-strip-shaped cold atomic group through cooling light, then spontaneous radiation four-wave mixing is used, Stokes photons and reversed Stokes photons are generated through pump light and coupling light, and the photons are collected. The line width of a narrow line width single photon source prepared by the two-dimensional magnetic optical trap system is in the megahertz magnitude, and the narrow line width single photon source is suitable for long-distance quantum communication.

The invention relates to a two-dimensional magnetic-optical trap system, which belongs to the field of neutral cold atom generation technology, and is characterized in that saddle-type reversed Helmholtz coils are adopted for forming the magnetic-optical trap system. The device is compact in integral mechanical structure and easy for miniatured and engineering application; by utilizing the inherent characteristics, such as compact structure, low installing precision requirement and better radial magnetic field gradient uniformity, of the saddle-type reversed Helmholtz coils, electricity power consumption required for forming a magnetic-optical trap is reduced; through controlling atom steam pressure intensity by electrified current, continuous cold atom sources with low speed, high throughput and small divergence angle are obtained, and a better engineering application platform is provided for an atomic frequency standard, an atom interference gyroscope or other cold atom physical experiments.

The invention provides a folding light path laser cooling atom device which is mainly composed of a vacuum tetrakaidecahedron, cooling light source assemblies, reflecting mirror assemblies, transfer mirror assemblies and anti-helmholtz magnetic field coils. The folding light path laser cooling atom device integrates a laser beam expansion collimation system, a folding light path, a polarization transformation system, the anti-helmholtz magnetic field coils and optical power real-time monitoring, six paths of laser required by a traditional laser cooling magneto optical trap is reduced to two paths of laser, the size and weight of an optical-mechanical system are reduced to the maximum degree, a space topology structure is simplified, and the optical-mechanical system is extremely good in mechanical property and thermal environment adaptability and can be applied to the severe environment of the space level. According to the folding light path laser cooling atom device, samples have passed ring die tests, such as a space level mechanical vibration test, a mechanical impact test, a thermal cycle test and a thermal vacuum test, long-term stable working can be kept, and the device can serve as a core optical-mechanical device of the laser cold atom application engineering.

The invention discloses a sensor and method for measuring a gravitational potential three-order differential quotient based on an atom interference effect, and relates to the technical field of cold atoms in atomic and molecular physical subjects. The sensor is composed of two cold atom interference devices, the central axes of two interference regions are overlapped, two vacuum containers are communicated into a whole in the direction of the central axes, and meanwhile a two-dimensional magneto-optical trap region is arranged. The measuring method is characterized in that the collecting process of a single set of original data points comprises the following steps that the two devices are used for emitting four synchronous faller cold atom groups, an initial state is prepared, synchronous correlation operations based on common Raman laser beams are carried out, and a final state is detected; the data processing process comprises the steps of converting n sets of original data points into n two-order phase difference data points and carrying out fitting processing. According to the system and the method, the influence of external interference and internal noise on measurement can be greatly restrained, and important significance is achieved for resource exploration, geologic structure analysis, physical geography study and other fields.

The invention relates to a method for acquirement an image of a single atom and especially relates to a detection method capable of realizing direct acquirement of an image of a single atom. The detection method capable of realizing direct acquirement of an image of a single atom solves the problem that during single atom imaging, detection is difficult because of strong background signals. The detection method capable of realizing direct acquirement of an image of a single atom comprises the following steps that 1, a quadrate quartz-made glass vacuum room is treated; 2, a light field part and a magnetic field part of a magneto-optical trap system are constructed; 3, a far red-detuned micro-optical dipolar trap is constructed; 4, after an exciting light is superposed with one of three light beams which are orthogonal, fluorescent lights produced by caesium atoms are collected by a lens unit, are reflected to an interference filter by a polarization beam splitter and enter into multimode fibers; and 5, the fluorescent lights produced by caesium atoms are collected by an aspherical mirror and are reflected to a camera of a charge-coupled device by a total reflective mirror forming an angle of 45 degrees with the horizontal plane; and an image of a single atom is obtained by adjustment of an imaging zone of the camera of the charge-coupled device. The detection method provided bythe invention can realize direct acquirement of an image of a single atom and can be widely utilized for the fields of control and measurement of a single atom, and quantum information.

The present disclosure provides a vacuum apparatus for miniaturizing an atomic interferometer. The appratus includes an upper window, a lower window, a square cavity, a connecting member, an atomic source component, a three-dimensional magneto-optical trap component, an interference component, and a detecting component. Fasteners matched with the upper and lower windows are sealed with thick glasscoated with anti-reflection coating on both faces, and systematic errors caused by wavefront distortion effects can be greatly reduced. Optical windows beyond the upper and lower windows are reasonably designed and are directly embedded into a vacuum chamber in a welded manner, a reasonable atomic cooling interference solution is adopted, and the vacuum apparatus are greatly reduced in size and weight and is simple and reliable in structure. A vacuum structure is properly modified and is also suitable for applications such as cold atomic gyroscopes, gravity gradiometers and the like.

The invention relates to atom laser cooling and atom laser capturing, in particular to a bi-color magneto-optical trap method and device for cooling and capturing atoms through lasers. According to the bi-color magneto-optical trap method and device, atom cooling and atom capturing are achieved through the bi-color lasers which work in a base-state, middle-excited-state and higher-excited-state cascading energy level, and atom pre-cooling is not needed. A step-type bi-color magneto-optical trap technology is adopted for the bi-color magneto-optical trap device, and the atoms can be directly cooled and captured from a vacuum air chamber. The step-type bi-color magneto-optical trap device can be used for cooling and capturing the alkali metal atoms, the alkaline earth metal atoms and even the rydberg atoms through the lasers; some quantum coherent effects can be directly researched in the cold atoms based on step-type bi-color dual-photon cooling, for example, the problem that correlation photon pairs are directly generated in bi-color magneto-optical traps is researched based on the rhombus-energy-level four-wave mixing effect; as for the experimental device, a bi-color magneto-optical trap experiment idea which is quite flexible and easy to achieve is initiated, and the experimental device can be conveniently applied and popularized.

The invention provides a vacuum device for atomic interference gravity measurement, which comprises a two-dimensional magneto-optical trap component, a three-dimensional magneto-optical trap component, an interference component, a detection component and an optical component, wherein the two-dimensional magneto-optical trap is used for atom two-dimensional cooling; the three-dimensional magneto-optical trap component is a tetrakaidecahedron after eight vertex angles are cut from a cube for three-dimensional cooling for atoms after two-dimensional cooling and tossing cooled atoms; the interference component is a cylindrical hollow pipeline for Raman laser incidence; the interference component enables interference to happen to the atoms under mutual effects of stimulated Raman transition laser and tossed atoms; the detection component is cubic for detecting the transition probability of atoms after interference; and the optical component is used for reflecting the incident Raman laser, and together with incident laser, a stimulated Raman transition laser pair is formed. The device height is greatly reduced, the weight of the device is lessened, the device is more flexible, and the stability is greatly enhanced.

The invention relates to an atomic space-adjustable dark magnetic optical trap method and device for preparing ultra cold polar molecules. With the method and device adopted, the technical problem of little possibility for atomic groups to realize space absolute overlap in a current ultra cold polar molecule preparing process can be solved. According to the method and device of the invention, trapping light of A atoms and B atoms are merged into one beam through corresponding optical components; the beam is divided into six beams; the six beams and an inverse helmholtz magnetic field form a magnetic optical trap, so that the overlap ratio of an A atom group and a B atom group trapped by the magnetic optical trap can be significantly enhanced; in a dark magnetic optical trap which is formed by depumping light through adopting a dark point, the intensity ratio of two beams of mixed light can be adjusted through adjusting several wave plates, particular, a third wave plate, and therefore, the work of the overlap of the two atom groups can be controlled, and an ideal condition can be created for the association of the atom groups; a user can know how to adjust the intensity ratio of beams of mixed light through observing atom group images acquired by a CCD image sensor, so that the overlap of the two atom groups can be realized, and the rate and yield of ultra cold polar molecule preparation can be effectively improved.

A two-dimensional (2D) magneto-optical trap (MOT) for alkali neutral atoms establishes a zero magnetic field along the longitudinal symmetry axis. Two of three pairs of trapping laser beams do not follow the symmetry axes of the quadruple magnetic field and are aligned with a large non-zero degree angles to the longitudinal axis. In a dark-line 2D MOT configuration, there are two orthogonal repumping beams. In each repumping beam, an opaque line is imaged to the longitudinal axis, and the overlap of these two line images creates a dark line volume in the longitudinal axis where there is no repumping light. The zero magnetic field along the longitudinal axis allows the cold atoms maintain a long ground-state coherence time without switching off the MOT magnetic field, which makes it possible to operate the MOT at a high repetition rate and a high duty cycle.

An inertial sensing system includes a magneto-optical trap (MOT) that traps atoms within a specified trapping region. The system also includes a cooling laser that cools the trapped atoms so that the atoms remain within the specified region for a specified amount of time. The system further includes a light-pulse atom interferometer (LPAI) that performs an interferometric interrogation of the atoms to determine phase changes in the atoms. The system includes a controller that controls the timing of MOT and cooling laser operations, and controls the timing of interferometric operations to substantially recapture the atoms in the specified trapping region. The system includes a processor that determines the amount inertial movement of the inertial sensing system based on the determined phase changes in the atoms. Also, a method of inertial sensing using this inertial sensing system includes recapture of atoms within the MOT following interferometric interrogation by the LPAI.

The present invention relates to a superfluid gyroscope apparatus based on cold atom gas quantum vortex. The superfluid gyroscope apparatus comprises a vacuum system, a laser cooling and trapping system, an excitation system, a time sequence control system, an information detection system, and an angular velocity resolving system. According to the present invention, the laser is used to cool the atom to achieve the gas-state superfluid, such that the atom collision relaxation problem in the atomic spin gyroscope is effectively solved, and the disadvantage that the superfluid gyroscope based on the liquid He quantum vortex is difficult to control is effectively overcome; and the high-throughput cold atom beam scheme of the double magneto-optical trap is used, such that the damage of the background atom in the first-stage gas chamber on the second-stage gas chamber interference environment can be avoided, and the high-throughput easily-captured atoms can be provided for the second-stage gas chamber. The present invention belongs to the technical field of novel quantum gyroscopes, and the superfluid gyroscope apparatus can be used for the superfluid gyroscope design based on the cold atom gas.

The invention discloses a miniaturized atomic interference gyroscope and a measuring method. The gyroscope comprises a vibration isolation platform (01), a laser system (02), a vacuum chamber (03), atwo-dimensional magneto-optical trap (07), a pyramid type magneto-optical trap (09), a detection system (10), pre-cooling laser, a trapped laser beam, probe laser, re-pumped laser, compensated laser,blowing-away laser, a Raman laser beam pair, and a corresponding laser beam emitter and the like. In addition, according to a detecting method, a point source interferometry (PSI) technique is employed. A re-pumping laser device excite an alkali metal sample to obtain an alkali metal atomic group; an atom is captured in a pyramidal magneto-optical trap (11) by cooling and the like; after the atomfalls freely for a period of time, an extended atomic sphere is formed; and then a single extended atomic sphere is used for measuring the amount of rotation and acceleration simultaneously to realizethe gyroscope function. The miniaturized atomic interference gyroscope has a simple structure and a small size and has the high application value in the high-performance inertial navigation system.

The invention relates to an optical beam-expanding collimation system for a cold atom physical experiment system in a magneto-optical trap structure, an optical trap structure and other structures, which is formed by connecting a laser-introducing system, a beam-expanding collimation system and a detection system by a bracket. The invention provides a basis for the modularized design of the cold atom physical system, enhances the adjustment, the expansibility and the detectability of the cold atom physical system, and has the advantages of simple structure, small size, convenient mounting and adjustment, high adjustment precision and good stability.

A two-dimensional (2D) magneto-optical trap (MOT) for alkali neutral atoms establishes a zero magnetic field along the longitudinal symmetry axis. Two of three pairs of trapping laser beams do not follow the symmetry axes of the quadruple magnetic field and are aligned with a large non-zero degree angles to the longitudinal axis. In a dark-line 2D MOT configuration, there are two orthogonal repumping beams. In each repumping beam, an opaque line is imaged to the longitudinal axis, and the overlap of these two line images creates a dark line volume in the longitudinal axis where there is no repumping light. The zero magnetic field along the longitudinal axis allows the cold atoms maintain a long ground-state coherence time without switching off the MOT magnetic field, which makes it possible to operate the MOT at a high repetition rate and a high duty cycle.

Disclosed is a satellite-borne cold atom imprisoning-type acceleration measurement method. Alkali metal atoms are filled in a three-dimensional magnetic-optical trap, the three-dimensional magnetic-optical trap emits a beam of alkali metal atoms to the space, the alkali metal atoms are stopped by an oncoming laser beam and are introduced to central points of the laser beam and a magnetic field, the central point of the laser beam, the central point of the magnetic field and the mass center of a satellite coincide, and the intensity of the laser beam and the magnetic field is controlled to enable the position of a cold atom to be kept in the position of the mass center of the satellite. In the operation process of the satellite, when the action force on the satellite and the action force on the cold atom are different, the cold atom deviates from the mass center of the satellite, so that the control force of the laser and the magnetic field is changed, and corresponding control force of the laser and the magnetic field are applied to enable the cold atom to be back to position of the mass center. The variation of the control force of the laser and the magnetic field in the operation process of the satellite in the third step is measured, and acceleration of the cold atom relative to the mass center of the satellite, namely the acceleration of non-inertia force on the satellite is calculated. The satellite-borne cold atom imprisoning-type acceleration measurement method has the advantages of being high in measurement accuracy, high in engineering feasibility and simple in operation.

In some variations, a vapor-cell system comprises: a vapor-cell region configured to allow at least one vapor-cell optical path into a vapor phase within the vapor-cell region; a first electrode disposed in contact with the vapor-cell region; a second electrode that is electrically isolated from the first electrode; and a transparent ion-conducting layer interposed between the first electrode and the second electrode, wherein the transparent ion-conducting layer is optically transparent over a selected optical band of electromagnetic wavelengths. Some embodiments provide a magneto-optical trap or atomic-cloud imaging apparatus, comprising: the disclosed vapor-cell system; a source of laser beams configured to provide three orthogonal vapor-cell optical paths through the vapor-cell gas phase, to trap or image a population of cold atoms; and a magnetic-field source configured to generate magnetic fields within the vapor-cell region. Methods of use are also disclosed herein.

A cold atom all-optical state selection device comprises vacuum flange, an optical state-selecting region, a magneto-optical trap, and a cavity base connected in sequence from top to bottom; when thecold atomic fountain clock starts to work, based on the magneto-optical trap cooling, trapping to get cold atomic groups and simultaneously preparing the clock state during the throwing of the cold atomic groups. The invention not only greatly increases the number density of the clock state atoms, but also shortens the height of the whole clock, thereby greatly shortening the dead time of the intermittent clock, thereby achieving the purpose of shortening the cycle and improving the short-term stability of the cold atomic clock. The device has a simple structure and is easy to implement, and can be used as a core device of a laser cold atomic clock.

The invention relates to laser cooling and trapping of ladder-type energy level alkaline metal atoms by means of laser of two wavelengths, particularly relates to a magneto-optical trap method and a magneto-optical trap device for cooling and trapping atoms by utilizing a laser device with two wavelengths at an atom storage band and an optical communication band. The magneto-optical trap method comprises the steps of: constructing an atom vacuum chamber provided with light-transmitting quartz windows; constructing a magnetic field part of a magneto-optical trap; constructing a light path part of laser operating in a ground state and a middle excited state of alkaline metal atoms; and constructing a atomic fluorescence detection part composed of a charge-coupled device camera. According to the magneto-optical trap device, the atoms can be directly cooled and captured from the atom vacuum chamber at room temperature, the magneto-optical trap device can be used for cooling and trapping the alkaline metal atoms by means of laser with the atom storage band and the optical communication band, and can be applied to application research of a cooling mechanism for multiphoton cooling atoms and a quantum repeater based on four-wave mixing.

The invention belongs to the atom cooling technologies, and discloses a 2 dimensional magneto-optical trap apparatus which is reduced in size and mains high-velocity stream for a 3 dimensional magneto-optical trap. The invention provides a 2 dimensional magneto-optical trap apparatus which includes a vacuum cavity having an atom source, a first laser alignment beam expanding system which is intended for generating a cooling beam, a first reflector, a second laser alignment system which is intended for generating another cooling beam, a second reflector, two pairs of anti-Helmholtz coils which are intended for generating a magnetic field. The incoming direction of the cooling beam is tilted at a certain angle with respect to the long shaft direction off the vacuum cavity, such that the cooling beam generates a light intensity component in the long shaft direction of the vacuum cavity. The light intensity component serves as effective pushing light. And a cooling sub-beam having high flux is obtained without an extra pushing light. According to the invention, the 2 dimensional magneto-optical trap apparatus can obtain the cooling sub-beam which meets requirements for low longitudinal speed, narrow distribution of longitudinal speed and large flux of atoms, has a simple structure and small size, and realizes reduction in sizes of the magneto-optical trap atom cooling systems.

The invention discloses a method for realizing two-dimensional cold atom surface optic lattices by a circular aperture array and relates to the field of neutral cold atom laser imprison and cold atom optic lattices. The method is implemented by a laser source system, a focusing lens, a beam expanding lens, a sub-wavelength circular aperture array, two-dimensional cold atom surface optic lattices, magneto-optical trap atom optic viscose, an atom detector, a laser, a wave chopper, another focusing lens, an optical fiber and a computer system on the basis of near-field optic diffraction of the sub-wavelength circular aperture array. Laser light irradiates on the horizontally arranged sub-wavelength circular aperture and diffracts through the same, local reinforcing near optical fields distributed periodically are generated, and neutral cold atoms loaded can be effectively imprisoned, and two-dimensional cold atom surface optic lattices are realized. The method for realizing two-dimensional cold atom surface optic lattices can realize surface optic lattices of neutral cold atoms of different types, lattice constant is adjustable, principle is simple, operation is convenient, and application range is wide.

The present invention discloses a method, an apparatus and a system for eliminating the deposit of atoms on a Zeeman cooling window in a strontium atom optical clock. A strontium atom optical clock system is provided with, in a linear order along the direction of the atomic beam, an atomic pile which emits the atomic beam, a magneto-optical trap which confines the atoms and the Zeeman cooling window. In at least one area of the zones from an emission port of the atomic pile to the Zeeman cooling window, excluding the magneto-optical trap, the resonance light of to-be-removed atoms is used to irradiate the motion path of the atoms along a direction at an angle with the motion path of the strontium atom beam so that the atoms cannot reach the Zeeman cooling window. The present invention creates transverse velocity of the atoms through irradiation to prevent the atoms from reaching the Zeeman cooling window, effectively eliminating the deposit of the atoms on the glass of the Zeeman cooling window in an atomic optical clock system and maintaining the high transparency of the window glass.

In order to overcome the defect that the polarization of an input laser beam cannot be accurately adjusted and maintained by an existing beam expansion collimator, the invention provides a polarization-adjustable laser beam expansion collimator employing magnetic optical trap, optical trap and other structure cold atomic physical experiment systems. A polarization prism and a slide of which polarization axis can be independently and accurately adjusted are arranged in an optical path, the polarization state of a light beam input from a polarization-maintenance optical fiber can be accurately adjusted and maintained, the fluctuation of a laser power is reduced, the change of the polarization state of an emergent light beam caused by the polarization-maintenance optical fiber is eliminated,and the requirement of high-quality ultracold atom preparation is met.

A method and system for detecting ratios and amounts of isotopes of noble gases. The method and system is constructed to be able to measure noble gas isotopes in water and ice, which helps reveal the geological age of the samples and understand their movements. The method and system uses a combination of a cooled discharge source, a beam collimator, a beam slower and magneto-optic trap with a laser to apply resonance frequency energy to the noble gas to be quenched and detected.

The invention discloses a large-beam-current cold atom source based on a two-stage two-dimensional magneto-optical trap, and relates to cold atom sources in the field of cold atom physics. The cold atom source comprises a first-stage two-dimensional magneto-optical trap (10), a second-stage two-dimensional magneto-optical trap (20) and a corrugated pipe (30). The first-stage two-dimensional magneto-optical trap (10), the corrugated pipe (30), the second-stage two-dimensional magneto-optical trap (20) and a three-dimensional magneto-optical trap (40) are connected in sequence. The included angle theta between a first central axis (112) and a second central axis (212) is 0-30 degrees. According to the large-beam-current cold atom source, under the highest loading efficiency of the three-dimensional magneto-optical trap, the number of atoms can be increased, and the service life of atomic cloud can be prolonged, which has an obvious effect especially in the subsequent cooling process of the MOT; excellent atom sources can be provided for a precision measurement technology based on cold atoms.

The invention discloses a system for constructing an atom cooling-used two-dimensional nano local light field. The system is provided with a substrate for placing a nano particle array; an incident laser for emitting a laser beam to the nano particle array is arranged beside the substrate; a neutral atom magneto-optical trap optical adhesive is arranged above the nano particle array; and one side of the neutral atom magneto-optical trap optical adhesive is provided with a release laser for emitting a laser beam. Compared with the prior art, the system and the method have the following advantages that the local light field has a larger potential field gradient and a deeper optical trap depth, and atoms can be trapped more easily; the local light field has a smaller size, and the two-dimensional local light field of below 50nm can be realized easily; and the SiO2 (glass) is adopted to serve as a nano particle substrate, lighting can be reflected and transmitted, and the atom control mode is more diverse.