An external-pyramid-type mot-based atomic chip cold atom vacuum physical device

Abstract

The application discloses an atomic chip cold atom vacuum physical device based on an external pyramid MOT, which comprises a device support assembly, a magnetic field assembly, a fluorescence collection assembly, a probe light assembly, a pyramid MOT generating assembly, a vacuum assembly and a cooling light generating assembly which are installed on the device support assembly; the device support assembly comprises an upper base platform, a lower base platform and a support column which is supported between the upper base platform and the lower base platform; the upper base platform is provided with the magnetic field assembly, the fluorescence collection assembly, the probe light assembly, the pyramid MOT generating assembly and the vacuum assembly; and the lower base platform is provided with the cooling light generating assembly. The application has the advantages that atoms are cooled and directly collected at a position of interest on a chip, and the internal optical path structure of the cold atom vacuum physical device is greatly reduced, and the magnetic field system is simplified.

Description

Technical Field

[0001] The present invention belongs to the technical field of miniaturized cold atom vacuum physics sensors based on atomic chips, and in particular relates to an atomic chip cold atom vacuum physics device based on an external pyramid-shaped MOT. Background Art

[0002] An atom chip is a device in which microwires are patterned on a substrate using micro-nanofabrication techniques. These microwires can create micromagnetic traps near the chip surface for trapping cold atoms. Vacuum physics systems based on atom chips are used to control electric, magnetic, and optical fields to capture and manipulate cold atomic clouds, ultimately forming Bose-Einstein condensates. Potential applications include atomic clocks, atom interferometers, and quantum information processors. Despite significant progress in the development of atom chips in recent years, methods for loading on-chip magnetic optical traps (MOTs) remain highly inconvenient. Typically, the entire atom chip vacuum physics device requires an external MOT structure. Atoms are first trapped in a macroscopic external magneto-optical trap (MOT) away from the chip surface. This requires the generation of multiple laser beams in space. Even the commonly used mirror-MOT scheme requires the generation of four cooling laser beams, which necessitates complex optical path reversal structures or multiple fiber collimators within the cold atom vacuum physics device. On-chip magnetic traps can be created using a macroscopic coil external to the chip combined with integrated wires to form a U-MOT or Z-MOT. The atoms are then loaded into an external magnetic trap, whose position is altered by shifting the external bias magnetic field. Ultimately, the trap must be moved very precisely to transfer the atoms into the small MOT on the chip.

[0003] Existing atomic chip cold atom vacuum physics generation devices basically adopt the above method. The already disclosed "A Method and Device for Atomic Beam Generation for Atomic Chip" with patent publication number (CN1805650A) captures and cools the atomic source vapor beam ejected from the hot atom source nozzle through a three-dimensional magneto-optical trap composed of 6 cooling laser beams and a second pair of anti-Helmholtz coils. Its chip cold atom cooling mechanism almost covers the characteristics of traditional atomic chip vacuum physics devices. On the one hand, the external magneto-optical trap structure is a traditional 6-beam laser beam structure, and the atomic chip MOT generally adopts a mirror MOT with a 4-beam cooling light structure. The internal optical path return system of the device is too complicated; on the other hand, the two magneto-optical traps each have a pair of anti-Helmholtz coils, which increases the complexity and size of the device; most importantly, the two magneto-optical traps are too far apart, which is not conducive to manipulating the transfer of pre-cooled atoms to the chip MOT. Summary of the Invention

[0004] In order to solve the above-mentioned technical problems existing in the prior art, the present invention provides an atomic chip cold atom vacuum physics device based on an external pyramid-type MOT, which has the advantages that atoms are cooled and directly collected at the position of interest on the chip, and greatly reduces the internal optical path structure of the cold atom vacuum physics device and simplifies the magnetic field system.

[0005] The technical solution adopted in the present invention is:

[0006] An atomic chip cold atom vacuum physics device based on an external pyramid-type MOT is characterized by comprising a device support component (3) and a magnetic field component (1) mounted on the device support component (3), a fluorescence collection component (2), a detection light component (4), a pyramid MOT generation component, a vacuum component (6) and a cooling light generation component (7), wherein:

[0007] The device support assembly (3) comprises an upper base platform, a lower base platform (18), and a support column (15) supported between the upper base platform and the lower base platform (18); the upper base platform is provided with the magnetic field assembly (1), the fluorescence collection assembly (2), the detection light assembly (4), the pyramid MOT generation assembly, and the vacuum assembly (6); the lower base platform (18) is provided with the cooling light generation assembly (7);

[0008] The pyramid MOT generating assembly comprises an atomic chip (5), a triangular reflection prism (62) and a 1 / 4 glass slide (63); four triangular reflection prisms (62) are provided on a side of the atomic chip (5) facing the cooling beam (14); the 1 / 4 glass slide (63) is provided in a vertical light transmission area in the center of the surface of the atomic chip (5); the cooling beam (14) is vertically hit to the atomic chip (5) area from bottom to top; the cooling beam (14) forms four beams of horizontal reflection cooling light in the horizontal direction, two of which form horizontal reflection cooling laser beams, and form vertical incident cooling beams (67) and vertical reflection cooling light (66) in the vertical direction, wherein the four beams of horizontal reflection cooling laser beams are formed by the cooling light at the edge being reflected by the four triangular reflection prisms (62); the polarization direction is σ + The horizontal circular polarized cooling light (64) and the opposite polarization direction σ - The horizontal circularly polarized cooling light (65) forms a horizontal reflected cooling laser; the four beams of horizontal reflected cooling light form a 2D-MOT on a two-dimensional plane, and the vertical incident cooling light beam (67) and the vertical reflected cooling light (66) are formed by the vertically upward laser beam in the middle area being reflected from the surface of the atomic chip, and finally a 3D-MOT is formed under the atomic chip, and the atom (68) will be cooled and trapped at the intersection of these six laser beams.

[0009] Further, the magnetic field assembly (1) comprises an MOT coil (50), an X-direction bias magnetic field coil (55), a Y-direction bias magnetic field coil (56) and a Z-direction bias magnetic field coil (52), the MOT coil (55), the X-direction bias magnetic field coil (55), the Y-direction bias magnetic field coil (56) and the Z-direction bias magnetic field coil (52) are fixed on the integrated frame (8) through the MOT coil frame (49), the X-direction coil frame (54), the Y-direction coil frame (53) and the Z-direction coil frame (51) respectively, and the integrated frame (8) is connected to the upper platform base 18 through the support rod (13).

[0010] Further, the MOT coil (55) is composed of a pair of anti-Helmholtz coils, which is part of the magnetic optical trap, and is used to provide a quadrupole magnetic well for the cooling and trapping of cold atoms, and the magnetic well center magnetic field gradient needs to reach at least 10 G / cm; the X-direction bias magnetic field coil (55), the Y-direction bias magnetic field coil (56) and the Z-direction bias magnetic field coil (52) are each composed of a pair of Helmholtz coils, which are used to provide an external magnetic field for the magnetic optical trap on the atom chip (5) and adjust the position of the external pyramid MOT center.

[0011] Further, the vacuum assembly (6) comprises a glass vacuum cavity (32), a metal four-way cavity (36) with a light window, a valve-equipped rubidium bubble tube structure, a dispenser atom release structure, an ion pump (42), an exhaust copper pipe (38), an indium sealing pipe (25) and a support foot (40), the glass vacuum cavity (32) is connected to the top of the metal four-way cavity (36) through the indium sealing pipe (25) and the indium sealing flange (41), and high-strength soft sealing of the glass vacuum cavity (32) and the metal four-way cavity (36) is realized by metal indium sealing; the bottom of the metal four-way cavity (36) is fixed on the support foot (40), and the support foot (40) is installed on the lower base platform (18); the upper end surface of the vacuum cavity (32) is sealed by the atom chip (5), and the triangular reflection prism (62) is vacuum-sealed inside the vacuum cavity; the metal four-way cavity (36) is provided with the valve-equipped rubidium bubble tube structure, the dispenser atom release structure, the exhaust copper pipe (38) and the ion pump (42) on the four side surfaces respectively, and the valve-equipped rubidium bubble tube structure and the dispenser atom release structure and the exhaust copper pipe (38) and the ion pump (42) are arranged opposite to each other.

[0012] Further, one end of the getter copper tube (38) is connected with the outer sub-pump group through the flange interface (39), and the other end is connected with the side of the metal four-way cavity (36) through the CF16 flange (37); the ion pump (42) is connected with the side of the metal four-way cavity (36) through the CF35 flange (43), and is driven by high voltage through the high-voltage line and the high-voltage line interface (44).

[0013] Further, the valve-equipped rubidium bubble tube structure comprises a vacuum control valve (46), a CF16 vacuum flange (47), and a rubidium bubble copper tube (48) for placing a rubidium bubble; the rubidium bubble copper tube (48) is connected with the side of the metal four-way cavity (36) through the CF16 flange (45), and the rubidium bubble (16) is placed in the rubidium bubble copper tube (48) in advance; the vacuum control valve (46) and the CF16 vacuum flange (47) are arranged on the rubidium bubble copper tube (48).

[0014] Further, the dispenser atomic release structure comprises a feedthrough pin (26), a vacuum feedthrough flange (33), a CF35 connecting pipe (34), and a CF35 vacuum flange (35); one end of the CF35 connecting pipe (34) is provided with the vacuum feedthrough flange (33), and the vacuum feedthrough flange (33) is provided with the feedthrough pin (26); the other end of the CF35 connecting pipe (34) is connected with the side of the metal four-way cavity (36) through the vacuum flange (35).

[0015] Further, the probe light assembly (4) comprises a probe light lens frame (21), a probe light collimator (19), a first 1 / 4 glass adjusting ring mounting frame (22), a first 1 / 4 glass adjusting ring (24), a first corner cube reflector (23), a probe light beam (9), and a probe light reflecting lens (10); the probe light reflecting lens (10) is mounted on a support leg (13) through a probe light reflecting lens frame (11), and the bottom of the support leg (13) is fixed on an upper base platform; the first corner cube reflector (23) is fixed on the probe light lens frame (21), and the probe light beam (9) is located between the first corner cube reflector (23) and the probe light reflecting lens (10); the first 1 / 4 glass adjusting ring (24) is mounted on the first 1 / 4 glass adjusting ring mounting frame (22), and the first 1 / 4 glass adjusting ring mounting frame (22) is mounted on the probe light lens frame (21); the probe light collimator (19) is fixed on the probe light lens frame (21) through a flange block (20), and the probe light lens frame (21) is fixed on the upper base platform.

[0016] Furthermore, the cooling light generating assembly (7) includes a cooling light collimator (31), a second corner cone reflection prism (17), a second 1 / 4 glass slide adjustment ring mounting frame (30), a second 1 / 4 glass slide adjustment ring (29) and a cooling light beam (14); the laser collimator (31) is fixed to the cooling light mirror group frame through a crimping flange (28); the second corner cone reflection prism (17) is bonded to the cooling light mirror group frame; the cooling light mirror group frame is fixed to the lower base platform (18); and the second 1 / 4 glass slide adjustment ring (29) is fixed to the second 1 / 4 glass slide adjustment ring mounting frame (30).

[0017] Furthermore, the fluorescence collecting assembly (2) is locked on the upper base platform by means of M6 screws.

[0018] Compared with the prior art, the beneficial effects of the present invention are embodied in:

[0019] 1. The present invention proposes a simple atomic chip cold atom vacuum physics device, that is, four corner cone reflection prisms are attached to the surface of the chip. The four prisms form a pyramid MOT structure, and a pyramid-shaped square hole is formed in the middle where atoms need to be trapped. Finally, a single wide beam of incident light is reflected multiple times in the pyramid structure and converged to form a three-dimensional magneto-optical trap. A square 1 / 4 / glass slide is attached to the middle hole to form a set of appropriately polarized light beams required for magneto-optical trap capture.

[0020] 2. The present invention has the advantage that atoms are cooled and directly collected at the location of interest on the chip, and greatly reduces the internal optical path structure of the cold atom vacuum physics device and simplifies the magnetic field system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The overall structure of the pyramid atomic chip vacuum physics device;

[0022] Figure 2 Cross-section of the Pyramid Atom Chip vacuum physics device;

[0023] Figure 3 Schematic diagram of the vacuum component of the physical device;

[0024] Figure 4 Schematic diagram of the magnetic field components of the Pyramid Atomic Chip vacuum physics device;

[0025] Figure 5 Pyramid atomic chip MOT structure;

[0026] Figure 6 Pyramid chip MOT schematic diagram.

[0027] Attachment Figure 1 Reference numerals:

[0028] 1-magnetic field component, 2-fluorescence collection component, 3-device support component, 4-detection light component, 5-atom chip, 6-vacuum component, 7-cooling light generation component.

[0029] Attachment Figure 2 Reference numerals:

[0030] 8- Overall frame of magnetic field system, 9- Detection beam, 10- Detection light reflective lens, 11- Detection light reflective mirror frame, 12- Support foot of detection light reflective mirror assembly, 13- Support rod of magnetic field system, 14- Cooling beam, 15- Upper and lower platform connecting rod, 16- Rubidium bulb, 17- Cooling light system corner cube prism, 18- Base platform, 19- Detection light collimator, 20- Collimator press-fit flange block, 21- Mechanical frame of light generation system, 22- 1 / 4 glass slide fixing frame, 23- Detection light corner cube reflective prism, 24- 1 / 4 glass slide adjustment ring, 25- Indium seal pipe, 26- Feedthrough pin, 27- Cooling light window, 28- Press-fit flange for indicating light window, 29- 1 / 4 glass slide adjustment ring for cooling light module, 30- 1 / 4 glass slide mounting frame, 31- Cooling light collimator.

[0031] Attachment Figure 3 Reference numerals:

[0032] 32-Glass vacuum chamber, 33-CF35 feedthrough flange, 34-Vacuum pipe with CF35 flanges on both ends, 36-4-way with light-through window, 37-CF16 flange, 38-Copper pipe for vacuum external pump group, 39-KF callan interface, 40-Vacuum system support base, 41-Indium seal flange, 42-Ion pump, 43-CF35 flange, 44-Ion pump high-pressure interface, 45-CF16 flange, 46-Rubidium source control valve, 47-CF16 flange, 48-Copper tube for placing rubidium bubble.

[0033] Attachment Figure 4 Reference numerals:

[0034] 49-MOT coil fixing frame, 50-MOT coil, 51-Z direction bias magnetic field fixing frame, 52-Z direction bias magnetic field coil, 53-Y direction bias magnetic field coil fixing frame, 54-X direction coil fixing frame, 55-X direction bias magnetic field coil, 56-Y direction bias magnetic field coil.

[0035] Attachment Figure 5 Reference numerals:

[0036] 57-chip PCB chip wire pin pin, 58-chip wire pin, 59-chip wire, 60-PCB chip connecting board, 61-chip gold plating layer, 62-corner cone reflection prism, 63-1 / 4 glass slide.

[0037] Attachment Figure 6 Reference numerals:

[0038] 64 - horizontally reflected cooling light 1, 65 - horizontally reflected cooling light 2, 66 - vertically reflected cooling light, 67 - vertically incident cooling light, 68 - atoms. DETAILED DESCRIPTION

[0039] The following describes the specific implementation of the embodiment of the present invention in detail with reference to the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the embodiment of the present invention and is not used to limit the embodiment of the present invention.

[0040] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0041] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with exemplary embodiments.

[0042] refer to Figures 1 to 6 The present invention provides an atomic chip cold atom vacuum physics device based on an external pyramid-type MOT, comprising a device support component 3 and a magnetic field component 1, a fluorescence collection component 2, a detection light component 4, a pyramid MOT generation component, a vacuum component 6, and a cooling light generation component 7 installed on the device support component 3, wherein:

[0043] The device support assembly 3 includes an upper base platform, a lower base platform 18, and a support column 15 supported between the upper base platform and the lower base platform 18; the upper base platform is provided with the magnetic field assembly 1, the fluorescence collection assembly 2, the detection light assembly 4, the pyramid MOT generation assembly 5, and the vacuum assembly 6; the lower base platform 18 is provided with the cooling light generation assembly 7;

[0044] The pyramid MOT generating assembly includes an atomic chip 5, a triangular reflection prism 62 and a 1 / 4 / glass slide 63. Four triangular reflection prisms 62 are provided on the side of the atomic chip 5 facing the cooling beam 14. The 1 / 4 glass slide 63 is provided in the vertical light transmission area in the center of the surface of the atomic chip 5; the cooling beam 14 is vertically hit to the atomic chip 5 area from bottom to top, and the cooling beam 14 forms 4 beams of horizontally reflected cooling light in the horizontal direction, and two of them form horizontally reflected cooling laser beams, and form vertically incident cooling beams 67 and vertically reflected cooling light 66 in the vertical direction, wherein the 4 beams of horizontally reflected cooling laser beams are formed by the cooling light at the edge reflected by the four triangular reflection prisms 62; the polarization direction is σ + The horizontal circular polarized cooling light 64 and the opposite polarization direction σ -The horizontal circularly polarized cooling light 65 forms a horizontal reflected cooling laser; the four beams of horizontal reflected cooling light form a 2D-MOT on a two-dimensional plane, and the vertically incident cooling light beam 67 and the vertically reflected cooling light 66 are formed by the vertically upward laser beam in the middle area reflected by the surface of the atomic chip, and finally a 3D-MOT is formed under the atomic chip. Atom 68 will be cooled and trapped at the intersection of these six laser beams.

[0045] In one embodiment, the magnetic field assembly 1 includes a MOT coil 50, an X-direction bias magnetic field coil 55, a Y-direction bias magnetic field coil 56 and a Z-direction bias magnetic field coil 52. The MOT coil 55, the X-direction bias magnetic field coil 55, the Y-direction bias magnetic field coil 56 and the Z-direction bias magnetic field coil 52 are respectively fixed on the integrated frame 8 through the MOT coil frame 49, the X-direction coil frame 54, the Y-direction coil frame 53 and the Z-direction coil frame 51. The integrated frame 8 is connected to the upper platform base 18 through the support rod 13.

[0046] In one embodiment, the MOT coil 55 is composed of a pair of anti-Helmholtz coils, which is part of a magneto-optical trap and is used to provide a quadrupole magnetic trap for cooling and trapping cold atoms. The magnetic field gradient at the center of the magnetic trap must be at least 10G / cm; the X-direction bias magnetic field coil 55, the Y-direction bias magnetic field coil 56 and the Z-direction bias magnetic field coil 52 are all composed of a pair of Helmholtz coils, which are used to provide an external magnetic field for the magneto-optical trap on the atomic chip 5 and adjust the position of the external pyramid MOT center.

[0047] In one embodiment, the vacuum assembly 6 includes a glass vacuum chamber 32, a metal four-way cavity 36 with a light-transmitting window, a valved rubidium bubble tube structure, a dispenser atom release structure, an ion pump 42, a vacuum copper tube 38, an indium seal pipe 25 and a support foot (40). The glass vacuum chamber 32 is connected to the top of the metal four-way cavity 36 through the indium seal pipe 25 and the indium seal crimping flange 41, and a high-strength soft seal between the glass vacuum chamber 32 and the metal four-way cavity 36 is achieved by metal indium sealing; the upper end surface of the vacuum chamber 32 is connected by The atomic chip 5 is sealed, and the triangular reflecting prism 62 is vacuum-sealed inside the vacuum cavity; the bottom of the metal four-way cavity 36 is fixed on the supporting foot 40, and the supporting foot 40 is installed on the lower base platform 18; the four sides of the metal four-way cavity 36 are respectively provided with the valved rubidium bubble tube structure, the dispenser atomic release structure, the vacuum copper tube 38 and the ion pump 42, and the valved rubidium bubble tube structure, the dispenser atomic release structure, the vacuum copper tube 38 and the ion pump 42 are arranged opposite to each other.

[0048] In one embodiment, one end of the vacuum copper tube 38 is connected to the external molecular pump group through a flange interface 39, and the other end is connected to the side of the metal four-way cavity 36 through a CF16 flange 37; the ion pump 42 is connected to the side of the metal four-way cavity 36 through a CF35 flange 43, and is driven by high voltage through a high-voltage line connection 44.

[0049] In one embodiment, the valved rubidium bubble tube structure includes a vacuum control valve 46, a CF16 vacuum flange 47, and a rubidium bubble copper tube 48 for placing the rubidium bubble. The rubidium bubble copper tube 48 is connected to the side of the metal four-way cavity 36 through the CF16 flange 45, and the rubidium bubble 16 is placed in the rubidium bubble copper tube 48 in advance; the vacuum control valve 46 and the CF16 vacuum flange 47 are provided on the rubidium bubble copper tube 48.

[0050] In one embodiment, the dispenser atomic release structure includes a feedthrough pin 26, a vacuum feedthrough flange 33, a CF35 connecting pipe 34 and a CF35 vacuum flange 35; one end of the CF35 connecting pipe 34 is provided with the vacuum feedthrough flange 33, and the vacuum feedthrough flange 33 is provided with the feedthrough pin 26; the other end of the CF35 connecting pipe 34 is connected to the side of the metal four-way cavity 36 through the vacuum flange 35.

[0051] In one embodiment, the detection light assembly 4 includes a detection light mirror group frame 21, a detection light collimator 19, a first 1 / 4 glass slide adjustment ring mounting frame 22, a first 1 / 4 glass slide adjustment ring 24, a first corner cone reflection prism 23, a detection beam 9 and a detection light reflecting lens 10, wherein the detection light reflecting lens 10 is mounted on a supporting foot 13 through a detection light reflecting mirror frame 11, and the bottom of the supporting foot 13 is fixed on the upper base platform; the first corner cone reflection prism 23 is fixed on the detection light mirror group frame 21, and the detection beam 9 is located between the first corner cone reflection prism 23 and the detection light reflecting lens 10; the first 1 / 4 glass slide adjustment ring 24 is mounted on the first 1 / 4 glass slide adjustment ring mounting frame 22, and the first 1 / 4 glass slide adjustment ring mounting frame 22 is mounted on the detection light mirror group frame 21; the detection light collimator 19 is fixed on the detection light mirror group frame 21 through a flange block 20, and the detection light mirror group frame 21 is fixed on the upper base platform.

[0052] In one embodiment, the cooling light generating assembly 7 includes a cooling light collimator 31, a second corner cone reflection prism 17, a second 1 / 4 glass slide adjustment ring mounting frame 30, a second 1 / 4 glass slide adjustment ring 29 and a cooling beam 14, the laser collimator 31 is fixed to the cooling light mirror group frame through a crimping flange 28, the second corner cone reflection prism 17 is bonded to the cooling light mirror group frame, the cooling light mirror group frame is fixed on the lower base platform 18, and the second 1 / 4 glass slide adjustment ring 29 is fixed to the second 1 / 4 glass slide adjustment ring mounting frame 30.

[0053] In one embodiment, the fluorescence collecting assembly 2 is locked on the upper base platform by M6 screws.

[0054] The operation process of the entire device of the present invention can be divided into the following steps in detail:

[0055] 1. Ultra-high vacuum is obtained;

[0056] First follow Figure 3 The model and the installation method of each component are used to construct an ultra-high vacuum system for a pyramid-shaped atomic chip vacuum physics device. The upper end face of the vacuum chamber is sealed by a pyramid-shaped chip MOT (atomic chip), and the pyramid corner cone prism structure (triangular reflection prism) is sealed inside the vacuum chamber. The PCB connection board is connected to the chip backplane by bonding. The PCB connection board is designed with a 2x2mm pad 60, which is connected to the via through a wire. The pin 57 is connected to the wire by welding on the via. The chip wire pin 58 is connected to the pad 60 on the PCB connection board by a "flying wire" method. After the entire atomic chip is successfully manufactured, it is bonded to the vacuum chamber 32 by glue. Finally, after the vacuum system is installed, the vacuum is connected to the external molecular pump unit through the exhaust copper tube 38 to start vacuuming. After reaching a certain vacuum degree, the intermittent copper tube 38 is disconnected from the external molecular pump unit, and the ion pump 41 is turned on separately to maintain the ultra-high vacuum of the entire vacuum system. Through simulation, the vacuum degree can reach 5e-8Pa ​​at this time.

[0057] 2. Atomic cooling and trapping;

[0058] After the ultra-high vacuum is obtained, the atom cooling and trapping experiment can be carried out. The MOT magnetic optical trap can be divided into an external pyramid type magnetic optical trap, a chip surface U-MOT and a chip surface Z-MOT. Firstly, a certain number of atom groups are trapped in the external pyramid type magnetic optical trap. Specifically, the MOT coil 50 and the cooling light beam 14 are turned on, and the atom groups are trapped in the middle of the corner cube prism. At this time, the center of the MOT is about 4 mm away from the chip surface. Then, the MOT magnetic field is turned off, the bias magnetic field is turned on, and the atom is further cooled through the polarization gradient cooling. Next, the atom group reaches a certain temperature, the Z-direction bias magnetic field is turned on to adjust the position of the MOT close to the chip surface, and then the external MOT magnetic field is turned off, the Y-direction bias magnetic field and the chip surface U line are turned on to form the chip surface U-MOT. At this time, the atom group is transferred to the U-MOT. Finally, the chip surface Z-MOT is turned on again, and the atom group is transferred to the Z-MOT for further cooling operation of the atom.

[0059] 3. Atomic state detection;

[0060] After the atom is cooled to a certain temperature through the above method, the atomic state detection is carried out by using the time-of-flight method. The time sequence control is set according to the falling time of the atom and the physical process. When the atom freely falls to the detection light beam 9, the detection light is turned on and a standing wave field is formed in space through the reflecting mirror 10. At this time, the atom located in this position is excited to the excited state by the detection light. Then, the atom returns to the ground state through spontaneous emission and releases photons. At this time, the fluorescence collection module collects the photon signal released by the atom due to spontaneous emission to calculate the temperature and quantity of the atom. The above process is the simple physical operation process of the whole device.

[0061] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0062] In addition, the terms "first", "second" are only for description purpose, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0063] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0064] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0065] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0066] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. An atomic chip cold atom vacuum physics device based on an external pyramid-shaped MOT, characterized in that: The invention comprises a device support component (3), a magnetic field component (1), a fluorescence collection component (2), a detection light component (4), a pyramid MOT generation component, a vacuum component (6), and a cooling light generation component (7) installed on the device support component (3), wherein: The device support assembly (3) includes an upper base platform, a lower base platform (18), and a support column (15) supported between the upper base platform and the lower base platform (18); the upper base platform is provided with the magnetic field assembly (1), the fluorescence collection assembly (2), the detection light assembly (4), the pyramid MOT generation assembly, and the vacuum assembly (6); the lower base platform (18) is provided with the cooling light generation assembly (7); The pyramid MOT generating assembly includes an atomic chip (5), a triangular reflection prism (62) and a 1 / 4 / glass slide (63), wherein the atomic chip (5) is provided with four triangular reflection prisms (62) on a side facing the cooling beam (14), and the 1 / 4 glass slide (63) is provided in the vertical light transmission area in the center of the surface of the atomic chip (5); the cooling beam (14) is vertically hit to the atomic chip (5) area from bottom to top, and the cooling beam (14) forms four beams of horizontal reflection cooling light in the horizontal direction, and two of them form horizontal reflection cooling laser beams, and form vertical incident cooling beams (67) and vertical reflection cooling light (66) in the vertical direction, wherein the four beams of horizontal reflection cooling laser beams are formed by the cooling light at the edge being reflected by the four triangular reflection prisms (62); the polarization direction is The horizontal circularly polarized cooling light (64) and the opposite polarization direction are The horizontal circularly polarized cooling light (65) forms a horizontal reflection cooling laser; the four beams of horizontal reflection cooling light form a 2D-MOT on a two-dimensional plane, and the vertical incident cooling light beam (67) and the vertical reflection cooling light (66) are formed by the vertical upward laser beam in the middle area being reflected by the surface of the atomic chip, and finally a 3D-MOT is formed under the atomic chip, and the atom (68) will be cooled and trapped at the intersection of these six laser beams; The detection light assembly (4) comprises a detection light mirror assembly frame (21), a detection light collimator (19), a first 1 / 4 glass slide adjustment ring mounting frame (22), a first 1 / 4 glass slide adjustment ring (24), a first corner cone reflection prism (23), a detection light beam (9) and a detection light reflection lens (10), wherein the first corner cone reflection prism (23) is fixed to the detection light mirror assembly frame (21), and the detection light beam (9) is located between the first corner cone reflection prism (23) and the detection light reflection lens (10).

2. The atom chip cold atom vacuum physics device based on an external pyramid-shaped MOT according to claim 1, characterized in that: The magnetic field assembly (1) comprises a MOT coil (50), an X-direction bias magnetic field coil (55), a Y-direction bias magnetic field coil (56) and a Z-direction bias magnetic field coil (52); the MOT coil (55), the X-direction bias magnetic field coil (55), the Y-direction bias magnetic field coil (56) and the Z-direction bias magnetic field coil (52) are fixed on an integrated frame (8) via a MOT coil frame (49), an X-direction coil frame (54), a Y-direction coil frame (53) and a Z-direction coil frame (51), respectively; and the integrated frame (8) is connected to an upper platform base via a support rod.

3. The atom chip cold atom vacuum physics device based on an external pyramid-shaped MOT according to claim 2, characterized in that: The MOT coil (50) is composed of a pair of anti-Helmholtz coils, which is part of the magneto-optical trap and is used to provide a quadrupole magnetic trap for cooling and trapping cold atoms. The magnetic field gradient at the center of the magnetic trap must be at least 10G / cm. The X-direction bias magnetic field coil (55), the Y-direction bias magnetic field coil (56) and the Z-direction bias magnetic field coil (52) are all composed of a pair of Helmholtz coils and are used to provide an external magnetic field for the magneto-optical trap on the atomic chip (5) and adjust the position of the external pyramid MOT center.

4. The atom chip cold atom vacuum physics device based on an external pyramid-shaped MOT according to claim 1, characterized in that: The vacuum assembly (6) comprises a glass vacuum cavity (32), a metal four-way cavity (36) with a light-transmitting window, a valved rubidium bubble tube structure, a dispenser atom release structure, an ion pump (42), an exhaust copper tube (38), an indium seal pipe (25) and a support foot (40). The glass vacuum cavity (32) is connected to the top of the metal four-way cavity (36) through the indium seal pipe (25) and the indium seal crimping flange (41), and a high-strength soft seal between the glass vacuum cavity (32) and the metal four-way cavity (36) is achieved by metal indium sealing. The upper end surface of the glass vacuum cavity (32) is sealed by the original The sub-chip (5) is sealed, and the triangular reflecting prism (62) is vacuum-sealed inside the vacuum cavity; the bottom of the metal four-way cavity (36) is fixed on the supporting foot (40), and the supporting foot (40) is installed on the lower base platform (18); the valved rubidium bubble tube structure, the dispenser atomic release structure, the vacuum copper tube (38) and the ion pump (42) are respectively arranged on the four sides of the metal four-way cavity (36), and the valved rubidium bubble tube structure, the dispenser atomic release structure, the vacuum copper tube (38) and the ion pump (42) are arranged opposite to each other.

5. The atom chip cold atom vacuum physics device based on an external pyramid-shaped MOT according to claim 4, characterized in that: One end of the vacuum copper tube (38) is connected to the external molecular pump group through a flange interface (39), and the other end is connected to the side of the metal four-way cavity (36) through a CF16 flange (37); the ion pump (42) is connected to the side of the metal four-way cavity (36) through a CF35 flange (43), and is driven by high voltage through a high-voltage line connected to a high-voltage line interface (44).

6. The atom chip cold atom vacuum physics device based on an external pyramid-shaped MOT according to claim 4, characterized in that: The valved rubidium bubble tube structure comprises a vacuum control valve (46), a CF16 vacuum flange (47), and a rubidium bubble copper tube (48) for placing the rubidium bubble. The rubidium bubble copper tube (48) is connected to the side of the metal four-way cavity (36) through the CF16 flange (45). The rubidium bubble (16) is placed in the rubidium bubble copper tube (48) in advance. The vacuum control valve (46) and the CF16 vacuum flange (47) are provided on the rubidium bubble copper tube (48).

7. The atom chip cold atom vacuum physics device based on an external pyramid-shaped MOT according to claim 4, characterized in that: The dispenser atomic release structure includes a feedthrough pin (26), a vacuum feedthrough flange (33), a CF35 connecting pipe (34) and a CF35 vacuum flange (35); one end of the CF35 connecting pipe (34) is provided with the vacuum feedthrough flange (33), and the vacuum feedthrough flange (33) is provided with the feedthrough pin (26); the other end of the CF35 connecting pipe (34) is connected to the side of the metal four-way cavity (36) through the vacuum flange (35).

8. The atom chip cold atom vacuum physics device based on an external pyramid-shaped MOT according to claim 1, characterized in that: The detection light reflecting lens (10) is mounted on a supporting foot (13) via a detection light reflecting lens frame (11), and the bottom of the supporting foot (13) is fixed on the upper base platform; the first 1 / 4 glass slide adjustment ring (24) is mounted on the first 1 / 4 glass slide adjustment ring mounting frame (22), and the first 1 / 4 glass slide adjustment ring mounting frame (22) is mounted on the detection light mirror group frame (21); the detection light collimator (19) is fixed on the detection light mirror group frame (21) via a flange block (20), and the detection light mirror group frame (21) is fixed on the upper base platform.

9. The atom chip cold atom vacuum physics device based on an external pyramid-shaped MOT according to claim 1, characterized in that: The cooling light generating assembly (7) comprises a cooling light collimator (31), a second corner cone reflection prism (17), a second 1 / 4 glass slide adjustment ring mounting frame (30), a second 1 / 4 glass slide adjustment ring (29) and a cooling light beam (14), wherein the cooling light collimator (31) is fixed to the cooling light mirror assembly frame via a crimping flange (28), the second corner cone reflection prism (17) is bonded to the cooling light mirror assembly frame, the cooling light mirror assembly frame is fixed to the lower base platform (18), and the second 1 / 4 glass slide adjustment ring (29) is fixed to the second 1 / 4 glass slide adjustment ring mounting frame (30).

10. The atom chip cold atom vacuum physics device based on an external pyramid-shaped MOT according to claim 1, characterized in that: The fluorescence collecting assembly (2) is locked on the upper base platform via M6 screws.

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