57 results about "Magneto-optical trap" patented technology

A compact grating-mirror magneto-optical trap (GMOT) cold atom inertial sensor head is disclosed. To make the sensor head compatible with the high vibration levels encountered in dynamic environments, the number of optical ports in the vacuum chamber is minimized and various components, including fixed optical components and a reflective grating chip, are hard mounted within the vacuum chamber. The use of the reflective grating chip reduces the number of optical ports required for cooling beams from six to one. The number of optical ports is further reduced by time multiplexing multiple beams passing through a given optical port.

The application discloses a three-dimensional magnetic optical trap device capable of adjusting cold atom projection speed, comprising a vacuum cavity, wherein an alkali metal source, a first reflector, a second reflector and a third reflector are arranged in the vacuum cavity; a first transmission window piece, a second transmission window piece and a third transmission window piece are arranged on the vacuum cavity; and a cold atom projection adjusting method is disclosed. The six lasers required by the traditional magnetic optical trap are reduced to three lasers through the reflectors integrated in the vacuum cavity, the volume and weight of the system are greatly reduced, the space structure is simplified, the stability of the device is improved, the device can be applied to the fields of atomic sensing technology and atomic clock and the like, and the integration degree of the instrument is improved.

The invention relates to the field of cold atom physical precision experiments, in particular to a high-collimation and low-power-consumption stable atomic furnace. Comprising a heat shielding cover, a transmitting tube is installed at the bottom of the heat shielding cover, one end of the transmitting tube located in a cavity is connected with a collimator through a connecting piece II, the outer side of the collimator is wound with a heating wire II, and the upper end of the collimator is connected with an atomic container; the outer sides of the atom container, the collimator and the connecting piece II are jointly sleeved with a heating layer, and a heating wire I is wound on the outer wall of the heating layer; three shielding layers are sequentially arranged in a cavity between the heating layer and the heat shielding cover from inside to outside; according to the invention, the atomic flux is ensured, the divergence angle and speed distribution of the emitted atoms are enabled to be within the capture range of the magneto-optical trap to a large extent, and the collimation of the atomic furnace is improved; the design of three heat shielding layers and the heat shielding cover is adopted, high polishing treatment is carried out on the heat shielding layers and the heat shielding cover, heat loss is reduced, temperature fluctuation stability is improved, power consumption is reduced, and stability is improved.

The invention relates to a light reflector element having several reflector surfaces which are aligned at an angle to a predefined direction of light incidence of the light reflector element, wherein the reflector surfaces can be arranged ring-shaped around a center of the light reflector element at a uniform angular distance to each other, wherein the reflector surfaces are arranged opposite each other with respect to the center of the light reflector element, so that light incident in the direction of light incidence (L) is deflected by the reflector surfaces into light rays which run towards each other in different spatial directions and meet in a central axis which runs through the center in the direction of light incidence. The invention further relates to a reflector arrangement with at least two such reflector elements and a quantum gradiometer. In general, the invention relates to the field of atom interferometers, in particular with magneto-optical traps (MOTs). In particular, the invention relates to atom interferometric gravimeters and gradiometers formed therewith.

The invention relates to the technical field of optical atomic clocks, and discloses a multi-mode magnetic field generation and regulation device and method for a strontium atom optical clock, and the device comprises a three-dimensional magnetic field coil, a magnetic field control system, and a magneto-optical trap. The three-dimensional magnetic field coil comprises an X-direction magnetic field coil, a Y-direction magnetic field coil and a Z-direction magnetic field coil; the X-direction magnetic field coil, the Y-direction magnetic field coil and the Z-direction magnetic field coil are mutually orthogonal and are respectively arranged along opposite positions to form a cubic framework, and the magneto-optical trap is positioned in the cubic framework; the magnetic field control system is electrically connected with the X-direction magnetic field coil, the Y-direction magnetic field coil and the Z-direction magnetic field coil. The technical problems that an existing strontium atom optical clock system is complex in structure and high in power consumption and thermal load, and time sequence characteristics used by a magnetic field in the operation process of the optical clock are not fully utilized are solved.

The invention discloses an integrated cold atom gravity measurement system based on a grating magneto-optical trap chip. The system mainly comprises an ion pump, a metal vacuum cavity, a transparent ultrahigh vacuum cavity, the grating magneto-optical trap chip, a chip fixing frame, an atom source and a matched light path assembly. In order to solve the problems that an existing three-dimensional magneto-optical trap system is complex in structure and low in integration level, a plane grating magneto-optical trap chip is introduced, the system configuration is effectively simplified, the space utilization rate is improved, and the atom capturing efficiency and purity are remarkably improved. The system has obvious advantages in atomic control performance and integration degree, specifically, efficient cooling and capturing, low power consumption, low noise and good detection performance, and an advanced solution is provided for realizing high-precision and miniaturized gravity measurement.

The invention provides quantum space-time reference integrated measurement equipment, method and system, the equipment comprises a detection device and a control terminal, the detection device comprises a magnetic shielding cylinder, a magneto-optical trap cavity is arranged in the magnetic shielding cylinder, different functional areas are integrated in the magneto-optical trap cavity, and each functional area comprises a cooling cavity in which cooling light and pump light are arranged; the microwave cavity is used for performing Ramsey primary interference after performing initial state preparation on the cold atomic group to obtain a frequency error signal between the output frequency of the local oscillator and the standard frequency; the second-stage interference region is arranged vertically below the free falling outlet of the atoms of the microwave cavity and is used for performing M-Z second-stage interference; the detection area is arranged at the tail end of the detection device and is communicated and connected with the secondary interference area; the control terminal is in communication connection with the detection device. According to the invention, synchronous measurement of time and space reference can be realized, the equipment reference transmission error and the equipment cost are reduced, and the test efficiency of space-time reference information is improved.

The invention particularly relates to a method for improving the frequency measurement accuracy of an optical lattice clock in a microgravity environment, which comprises the following steps of: splitting two beams of lattice light through a lattice light laser, respectively splitting two beams of lattice light from each beam of lattice light, and forming two one-dimensional horizontal optical lattices by four beams of lattice light; wherein a certain distance exists between the beam waist positions of the two one-dimensional horizontal optical lattices in the vertical direction, the midpoint position of the two one-dimensional horizontal optical lattices is the position of a magnetic field zero point in the magneto-optical trap, the projections of the axial directions of the two horizontal optical lattices in the vertical plane are parallel to each other, and the projections of the axial directions of the two horizontal optical lattices in the horizontal plane are perpendicular to each other; an acousto-optic modulator with identical parameters is loaded on a light path of each beam of lattice light and is used for linear frequency shift and modulation of lattice light frequency; two beams of clock laser are split by a clock laser light source to respectively excite different atomic groups in two one-dimensional horizontal optical lattices. Differential comparison of transition frequencies of different atomic group clocks is realized by synchronously detecting transition spectrum lines of different atomic group clocks, so that common-mode noise in an optical clock system is suppressed. According to the method, the optical lattice clock with ultra-high frequency measurement precision in a microgravity environment can be realized.

The invention belongs to the related field of atom interference differential measurement devices, and discloses an atom interference differential measurement device for realizing a high-consistency double-atom fountain, which comprises a first interference unit, a first atom preparation and detection unit, a second interference unit and a second atom preparation and detection unit which are arranged in sequence, wherein the first interference unit and the second interference unit are respectively used for providing spaces for an atom interference process; and the first atom preparation and detection unit and the second atom preparation and detection unit are respectively used for forming horizontal trapping light and realizing atom trapping of the two three-dimensional magneto-optical traps together with the vertical trapping light. According to the invention, the structure of the whole device is further compact, atom trapping of two magneto-optical traps can be realized only by inputting three beams of trapping light, and the same pair of vertical trapping light can be utilized in the two trapping modules to carry out upthrowing operation on atoms, so that high-synchronism double-substance wave source preparation can be realized; the common-mode effect in atomic interference measurement can be better inhibited, and the requirement for optical power is greatly reduced.

The application provides a quantum space-time reference integrated measurement device, method and system, wherein the device comprises a detection device and a control terminal, the detection device comprises a magnetic shielding cylinder, a magneto-optical trap cavity is arranged in the magnetic shielding cylinder, and different functional areas are integrated in the magneto-optical trap cavity; the functional areas comprise: a cooling cavity, wherein a cooling light and a pumping light are arranged; a microwave cavity, which is used for performing Ramsey first-order interference on a cold atom group after initial state preparation to obtain a frequency error signal between a local oscillator output frequency and a standard frequency; a second-order interference area, which is arranged vertically below an atom free-fall outlet of the microwave cavity and is used for performing M-Z second-order interference; a detection area, which is arranged at the end of the detection device and is connected with the second-order interference area; and the control terminal is in communication connection with the detection device. The application can realize synchronous measurement of time and space references, reduce reference transmission error and equipment cost of the device, and improve the test efficiency of space-time reference information.

A loading assembly for providing atomic objects to a confinement apparatus is provided. The loading assembly includes an oven configured to generate an atomic flux of an atomic species / isotope having a non-zero nuclear spin. The loading assembly includes mirror and magnet arrays configured to, when optical beams are provided to the arrays, generate a two-dimensional magneto-optical trap (2D MOT) with a simplified repumping scheme. The 2D MOT is configured to generate a substantially collimated atomic beam from the oven generated atomic flux.

The invention discloses a Raman grating magneto-optical trap gravimeter realized by pulse laser. The Raman grating magneto-optical trap gravimeter comprises a central controller, a coherent laser generator and a grating magneto-optical trap gravimeter, the central controller controls the coherent laser generator and is used for outputting control voltage so as to control operation of the seed light laser, the optical fiber electro-optical modulator, the pulse laser generator, the multi-stage optical fiber amplifier and the optical fiber acousto-optic modulator. The seed light laser outputs continuous laser to be injected into the optical fiber electro-optical modulator; the optical fiber electro-optical modulator adopts a radio frequency signal to modulate input continuous laser and then injects the continuous laser into the pulse laser generator; the pulse laser generator continuously converts laser into short-pulse laser and injects the short-pulse laser into the multi-stage optical fiber amplifier; a frequency doubling crystal after short pulse laser amplification; frequency is increased and converted into the required laser wavelength, the laser wavelength is injected into the optical fiber acousto-optic modulator, and the output of the optical fiber acousto-optic modulator is injected into the grating magneto-optical trap gravimeter. The device is simple in structure and low in cost, and the research, development, production and application cost of the device is reduced.

Quantum memory The invention relates to an assembly (11) for a quantum memory (10), the quantum memory (10) being suitable to store and retrieve a quantum information encoded into an optical signal, the assembly (11) being deprived of optical cavity and comprising: - a vacuum chamber (12), - a neutral atoms source (14) suitable to generate neutral atoms in the vacuum chamber (12), and - a magneto-optical trap generator (16) suitable to generate an elongated magneto-optical trap enabling to trap neutral atoms in the vacuum chamber (12) so as to obtain an elongated ensemble of neutral atoms elongated along a so-called elongation axis, the elongation axis being along a vertical direction, the optical signal being intended to propagate in the vacuum chamber (12) along the elongation axis, the quantum information being stored in the elongated ensemble of neutral atoms or being retrieved from the elongated ensemble of neutral atoms depending on a control signal.

A double-layer atom chip gyroscope is composed of two layers of atom chips, the surface chip structure can generate a closed smooth guiding center with no magnetic field zero point ring magnetic guide; the bottom chip can generate a hierarchical transition magnetic trap, so that the cold atom group is smoothly and efficiently loaded into the ring magnetic guide from the macroscopic magnetic optical trap, while increasing the magnetic trap in the ring waveguide angle direction. Through the cooperation of the two layers of chips in time sequence, when the cold atom group is loaded into the ring magnetic guide from the dimple trap formed by the bottom chip, the angular restraint of the magnetic trap to the cold atom group disappears, the radial restraint increases, and the cold atom group provides additional angular momentum, realizes the cold atom group ring beam, and detects the matter wave gyroscope effect. The wire layout of the two layers of chips is a plane structure, which is easy to etch on the chip surface and convenient to debug, and the system is robust.

The invention relates to an injection laser automatic frequency stabilization device and method based on cold atom imaging feedback. The device comprises a primary cooling light path, a secondary cooling light path, a charge-coupled device and a control module. The first-stage cooling light path and the second-stage cooling light path are used for outputting single longitudinal mode laser by using the seed laser, injecting the single longitudinal mode laser into the plurality of injection lasers and then outputting cooling laser into the vacuum system; the charge-coupled device is used for acquiring a cold atom cloud image in the magneto-optical trap of the vacuum system in real time; the control module is used for automatically locking the plurality of injection lasers to a single longitudinal mode state according to the brightness of the cold atom cloud image and a preset sequence; and according to the brightness change of the cold atom cloud image, judging the injection laser which is unlocked and re-locking the injection laser. The problems that a traditional injection locking system is large in size, insufficient in automation, dependent on manpower, poor in environmental adaptability and the like are solved.

The application discloses a kind of molecular sub-Doppler cooling magneto-optical trap design method based on artificial intelligence algorithm, belong to molecular laser cooling technical field.First, construct three-dimensional molecular magneto-optical trap scheme model, then solve the optical Bloch equation of three-dimensional molecular magneto-optical trap scheme model, obtain trapping and cooling acceleration from this;Further optimize trapping and cooling acceleration calculated by optical Bloch equation, to obtain the best parameter point that can simultaneously have trapping and cooling in preset speed and preset spatial range.The present application first introduces Bayesian optimization algorithm into molecular magneto-optical trap design, solves the big problem that has plagued molecular laser cooling, i.e.sub-Doppler heating effect in type II magneto-optical trap.Three-dimensional Monte Carlo simulation shows that the scheme can reduce the temperature of molecular magneto-optical trap to 40 μK, and its phase space density increases by two orders of magnitude, which is a key step to realize molecular Bose-Einstein condensation.

In this magneto-optical trap device, five laser beams are irradiated in a trap space in which atoms are trapped. Of the five laser beams, three laser beams (laser beams a1, a2, a3) pass through the inside of the same plane (Z plane) and are irradiated in the trap space. The two laser beams that intersect that plane (laser beams a4, a5) are irradiated in the trap space. The laser beam a1 is used together as a slowing laser beam b for Zeeman slower.

The invention discloses a compact double-magneto-optical trap device which is composed of a main frame, a glass vacuum cavity, a collimation assembly, a left magneto-optical trap, a right magneto-optical trap and the like. The structural sizes of the left magneto-optical trap and the right magneto-optical trap are reduced by improving the mounting mode of a collimator and a coil; the projection inclination angle is designed to ensure that the atomic group is projected to the center of the opposite magneto-optical trap to improve the repeated trapping efficiency of the atomic group; the invention further discloses an adjustment alignment device and an adjustment alignment method of the compact double-magneto-optical trap device, the optomagnetic coincidence precision is improved by introducing the metal hexahedron, the cooling temperature of an atomic group is further reduced, and finally the portable, compact and stable double-magneto-optical trap device is achieved.

A single-laser modulated small magneto-optical trap (MOT) comprises a laser. The main laser emitted by the laser is split and reflected to form a first cooling beam, a second cooling beam, a third cooling beam, and a feedback beam. The cooling beams form a MOT optical path in which six beams are emitted in pairs and converge at a point within a vacuum chamber. The MOT is formed under the influence of a gradient static magnetic field formed by a first magnetic field coil and a second magnetic field coil. The feedback beam passes through a rubidium vapor chamber and is converted into re-pumping light through a photoelectric probe, a modem, a frequency-locked controller, and an electro-optical modulator. The laser combines the re-pumping light with the generated main laser beam. The device features a low-complexity laser optical path, low cost, and high precision. The vacuum glass chamber has low scattering, high transparency, a low thermal expansion coefficient, and good vacuum sealing, providing excellent optical performance and stability while reducing the effects of magnetic field interference and thermal expansion.

The invention discloses a microwave electric field high-sensitivity measurement method based on Rydberg atom hysteresis trajectory folding, and the method comprises the steps: preparing a high-density cold atom ensemble through a magneto-optical trap, and constructing a two-photon transition path to excite a Rydberg state; regulating and inducing quantum phase change through a microwave field to generate a hysteresis track with an intersection point; in combination with a noise suppression algorithm and a critical point tracking technology, extracting a nonlinear offset of a trajectory intersection point, and establishing a quantitative mapping relation between the nonlinear offset and the microwave field intensity; the atomic density is optimized to enhance the interaction between Rydberg atoms, and the SQL limitation is broken through. The quantum phase change critical behavior and the multi-body effect are combined, sub-nanovolt sensitivity, wide-frequency-band compatibility and high anti-interference capacity are achieved, and a new normal form is provided for high-precision microwave electric field measurement, quantum metering and basic physical research.

A loading assembly for providing atomic objects to a confinement apparatus is provided. The loading assembly includes an oven configured to generate an atomic flux of an atomic species / isotope having a non-zero nuclear spin. The loading assembly includes mirror and magnet arrays configured to, when optical beams are provided to the arrays, generate a two-dimensional magneto-optical trap (2D MOT) with a simplified repumping scheme. The 2D MOT is configured to generate a substantially collimated atomic beam from the oven generated atomic flux.

The present invention discloses a microchip and method for preparing ultracold atoms. The microchip includes a chip substrate, an oxide isolation layer provided on the chip substrate, a wire etching layer provided by ion evaporation sputtering, and wires etched on the wire etching layer by photolithography. The wires are designed as double U-shaped wires and double H-shaped wires, with a groove size of 15 μm between the wires. The present invention uses the extremely high gradient potential well field generated by the double U-shaped and double H-shaped wires on the chip to trap and manipulate cold atoms on-chip. On the one hand, this method overcomes the limitations imposed by the large coils and complex optical paths of traditional magneto-optical traps on the optical system and magnetic field coils of miniaturized atomic vacuum physics units. On the other hand, the compact and steep potential well provides an effective way to further achieve on-chip rapid evaporative cooling to prepare ultracold atoms.

The invention relates to the field of neutral atom quantum computing, in particular to a three-dimensional magneto-optical trap system and a using method thereof. The three-dimensional magneto-optical trap system comprises a magnetic field adjusting assembly, a coil framework, a magneto-optical trap adjusting assembly and a supporting assembly. The magnetic field adjusting assembly is arranged above the coil framework, a vacuum cavity is formed in the coil framework, and the position of a magnetic field zero point in the vacuum cavity can be adjusted by adjusting the relative position of the magnetic field adjusting assembly and the coil framework, so that the center of a light path coincides with the magnetic field zero point to cool atoms; optical tweezer array light beams are received in the vacuum cavity through the strong focusing lens, the optical tweezer array is used for capturing and trapping cooled atomic groups to form a cold atom array, the magneto-optical trap adjusting assembly is arranged on the supporting assembly, and the positions of the cold atomic groups can be adjusted by adjusting the relative positions of the magneto-optical trap adjusting assembly and the supporting assembly. The center of the cold atomic group is enabled to coincide with the focus of the optical tweezers array, and the adjustment range and precision are optimized through the system.

The present invention discloses a double-T composite high-dynamic range atomic interferometry gravity measurement method and device, comprising: S1. Atom cooling: preparing a cold atomic cluster using a magneto-optical trap unit; S2. Atom initial state preparation: preparing an atomic ensemble in a single-component dual-momentum domain using an atomic velocity and state selection unit; S3. Double-T composite interference: after atoms enter an interference cavity, two groups of narrow-band Raman pulse sequences are used to respectively manipulate the atoms in two velocity domains to form a double-T composite interferometer; S4. Four-channel decoupling detection: using a combination of velocity-selective Raman pulses and energy-state-selective fluorescence resonance pulses to form a composite detection sequence, and using a photodetector to realize decoupling measurement of the atomic states of four output channels; S5. Raman light frequency or phase scanning: scanning the frequency or phase of the two groups of Raman light pulses of the double-T interferometer to form interference fringes; S6. Four-channel signal joint analysis: performing a joint analysis on the output signals of the four channels to calculate the gravitational acceleration value.

The application relates to a method for improving the frequency measurement precision of an optical lattice clock in a microgravity environment, which comprises the following steps: two beams of lattice light are divided from one lattice light laser, each beam of lattice light is further divided into two beams of lattice light, and four beams of lattice light form two one-dimensional horizontal optical lattices; wherein the waist positions of the two one-dimensional horizontal optical lattices have a certain interval in the vertical direction, and the midpoint position is the position of the magnetic field zero point in the magneto-optical trap; the projections of the axial directions of the two horizontal optical lattices in the vertical plane are parallel to each other, and the projections in the horizontal plane are perpendicular to each other; an acousto-optic modulator with the same parameters is loaded on the light path of each beam of lattice light, and is used for linear frequency shift and modulation of the lattice light frequency; two clock laser beams are divided from one clock laser source, and are used for exciting different atomic groups in the two one-dimensional horizontal optical lattices. By synchronously detecting the clock transition spectral lines of each different atomic group, the differential comparison of the clock transition frequencies of different atomic groups is realized, so that the common-mode noise in the optical clock system is suppressed. The method can realize an optical lattice clock with super-high frequency measurement precision in a microgravity environment.

The present disclosure provides a preparation device and preparation method of an identical single-photon source, and a preparation method of an entangled photon source. The preparation device of the identical single-photon source includes: a first laser, suitable for providing an initial laser beam; a magneto-optical trap, suitable for capturing and forming an atomic cluster; a modulation component, suitable for modulating the initial laser beam under the action of an external modulation signal to obtain multiple first laser beams; a first objective lens, suitable for focusing the multiple first laser beams so that the multiple first laser beams form multiple first light spots at the focus of the first objective lens, and the multiple first light spots form an optical dipole trap array, which is suitable for capturing atoms in the atomic cluster to form a single-atom array; and a waveguide array, suitable for collecting fluorescence generated by the single-atom array when excited by an externally input second laser beam, so as to form an identical single-photon source array assisted in collection by the waveguide array.

The present application relates to the technical field of optical atomic clock, and discloses a kind of for strontium atom optical clock Multi-mode magnetic field generation and regulation device and method, including three-dimensional magnetic field coil, magnetic field control system and magneto-optical trap;Three-dimensional magnetic field coil includes X direction magnetic field coil, Y direction magnetic field coil and Z direction magnetic field coil;X direction magnetic field coil, Y direction magnetic field coil and Z direction magnetic field coil mutually orthogonal and respectively along opposite position arrangement form cubic skeleton, and magneto-optical trap is located in cubic skeleton;Magnetic field control system is respectively with X direction magnetic field coil, Y direction magnetic field coil and Z direction magnetic field coil electric connection setting.The present application solves the technical problem that the existing strontium atom optical clock system structure is complex, power consumption and thermal load is higher, and not fully utilize the time sequence characteristics of magnetic field use in the process of optical clock operation.

According to the present invention, atoms are trapped by means of a quadrupole magnetic field formed by ring-shaped magnets (106), (108) and three sets of laser beam pairs. A portion of the laser beam pairs LZ is partially blocked by the ring-shaped magnets (106), (108), so that a region (114) which is a non-atom trap space is formed inside a intersecting region (112) where the three groups of laser beam pairs cross. The inside of the intersecting region (112) is irradiated with a laser beam (118) so that atoms within the non-atom catch space are extracted from intersecting region (112).

The application discloses a chip active optical clock based on grating magneto-optical trap cooling and an implementation method thereof. Three saturated absorption spectrum frequency stabilization DBR lasers are used to generate cooling laser, re-pumping laser and pumping laser respectively, wherein the cooling laser and the re-pumping laser cooperate with the grating magneto-optical trap, are used for cooling and confining atoms, and form a cold atom group in an atom chamber; the pumping laser excites the cold atoms, and the generated stimulated radiation signal is directly used as an optical frequency standard signal output, and after frequency beating with a microcavity optical comb, a chip active optical clock is realized. Compared with a traditional cold atom optical clock, the application greatly reduces the volume of the system, can be integrated on a chip, and is suitable for a compact and portable device application scene; compared with a current chip microwave atomic clock, the stability index of the application is higher. The application has important application value, and can provide a long-time and high-precision frequency reference for a movable device.

This invention belongs to the field of cold atom two-dimensional magneto-optical trap technology and discloses a highly integrated miniaturized cold atom two-dimensional magneto-optical trap module, including an atomic beam cavity, and further including: an assembly connecting plate, on which a first mounting area, a second mounting area, and a third mounting area are sequentially arranged along the center outward direction; and a coaxial locking component, which locks the assembly connecting plate, the magnetic field coil module, and the cooling optical module to a fixed relative position. This invention achieves spatial nesting of the magnetic field and optics by radially and coaxially integrating the atomic beam cavity, the magnetic field coil module, and the cooling optical module, forming an integrated module with a volume much smaller than traditional discrete structures. Simultaneously, the coaxial locking component presses and maintains the coaxiality of each functional module along the axial direction. During use, installation can be completed simply by docking with an external vacuum cavity, inserting optical fibers, and connecting plug-in terminals, eliminating the need for on-site debugging of the optical path and magnetic field position, greatly simplifying the assembly and adjustment process.