Flexible retro-reflected modulatable optical trap

Abstract

A system 100 (e.g. for a modulatable optical trap) including a retro-reflector 110 and an optical modulation unit 120 is described. A first laser beam 140 is optically coupled with a chamber 130 including particles 132. The optical modulation unit is between the retro-reflector and the chamber. The optical modulation unit is configured to provide in the chamber an optical dipole trap for a first set of operating conditions and an optical lattice for a second set of operating conditions. The optical dipole trap is formed by the first laser beam in an absence of a retroreflected laser beam from the retro-reflector. The optical lattice is formed from the first laser beam and a modulated retroreflected laser beam from the optical modulation unit. The optical modulation unit is thus configured to be capable of modulating intensity and phase. Also described is a system with acousto-optical modulators (AOM).

Description

BACKGROUND OF THE INVENTION

[0001] Techniques for trapping particles (e.g. neutral atoms, charged atoms (ions), and / or molecules) include optical traps. For example, an optical dipole trap can be formed using a laser beam of detuned light. A laser is detuned when the frequency is shifted from that of the resonance for the energy levels of the particle. An induced dipole in a particle allows weak trapping of the particle by the laser beam. An optical lattice is analogous to an optical dipole trap but is formed by multiple laser beams that intersect, forming an interference pattern. Particles can be trapped in this interference pattern. For example, two laser sources can provide counterpropagating laser beams. The counter-propagating laser beams interfere to form the lattice. Depending upon the number and orientation of the laser beams, a one-, two-, or three-dimensional lattice might be formed. Once the particles are trapped, the particles can be manipulated.

[0002] Although optical dipole traps and optical lattices can be used to trap atoms and other particles, there are drawbacks. For example, multiple laser paths may be time consuming to align and require additional power for operation. This may slow and complicate fabrication of the optical trap. Consequently, additional techniques for trapping particles are desired. BRIEF DESCRIPTION OF THE DRAWINGS

[0003] Various embodiments of the invention are disclosed in the following detailed description and the accompanying drawings.

[0004] FIGS. 1A-1B are block diagrams depicting an embodiment of a system for forming a flexible, modulated optical trap.

[0005] FIG. 2 is a diagram depicting an embodiment of a system for forming a flexible, modulated optical trap.

[0006] FIG. 3 is a flow chart depicting an embodiment of a method for forming a flexible, modulated optical trap.

[0007] FIG. 4 is a flow chart depicting an embodiment of a method for forming a flexible, modulated optical trap. DETAILED DESCRIPTION

[0008] The invention can be implemented in numerous ways, including as a process; an apparatus; a system; a composition of matter; a computer program product embodied on a computer readable storage medium; and / or a processor, such as a processor configured to execute instructions stored on and / or provided by a memory coupled to the processor. In this specification, these implementations, or any other form that the invention may take, may be referred to as techniques. In general, the order of the steps of disclosed processes may be altered within the scope of the invention. Unless stated otherwise, a component such as a processor or a memory described as being configured to perform a task may be implemented as a general component that is temporarily configured to perform the task at a given time or a specific component that is manufactured to perform the task. As used herein, the term ‘processor’ refers to one or more devices, circuits, and / or processing cores configured to process data, such as computer program instructions.

[0009] A detailed description of one or more embodiments of the invention is provided below along with accompanying figures that illustrate the principles of the invention. The invention is described in connection with such embodiments, but the invention is not limited to any embodiment. The scope of the invention is limited only by the claims and the invention encompasses numerous alternatives, modifications and equivalents. Numerous specific details are set forth in the following description in order to provide a thorough understanding of the invention. These details are provided for the purpose of example and the invention may be practiced according to the claims without some or all of these specific details. For the purpose of clarity, technical material that is known in the technical fields related to the invention has not been described in detail so that the invention is not unnecessarily obscured.

[0010] A system including a retro-reflector and an optical modulation unit is described. A first laser beam is optically coupled with a chamber including particles (e.g. neutral atoms). The optical modulation unit is between the retro-reflector and the chamber. The optical modulation unit is configured to provide in the chamber an optical dipole trap for a first set of operating conditions or an optical lattice for a second set of operating conditions. The optical dipole trap is formed by the first laser beam in an absence of a retroreflected laser beam from the retro-reflector. In some such embodiments, the optical modulation unit is configured to prevent the presence of the retroreflected beam in the chamber for the first set of operating conditions. The optical lattice is formed from the first laser beam and a modulated retroreflected laser beam from the optical modulation unit. The optical modulation unit is configured to modulate at least intensity and / or phase. In some embodiments, the optical modulation unit can phase modulate the retroreflected laser beam to shake the optical lattice.

[0011] For the second set of operating conditions, the optical modulation unit receives the first laser beam transmitted by the chamber and modulates the first laser beam to provide a second laser beam including a modulated first laser beam. The retro-reflector retroreflects the second laser beam toward the optical modulation unit in a counter-propagating direction. The optical modulation unit modulates the retroreflected laser beam to provide the modulated retroreflected laser beam to the chamber for the second set of operating conditions.

[0012] In some embodiments, the optical modulation unit further includes a first acousto-optical modulator (AOM) and a second AOM. The first AOM is between the chamber and the second AOM. The first AOM may provide a first frequency shift, while the second AOM may provide a second frequency shift opposite to the first frequency shift such that the interference of the lattice at the position of the atoms may be stationary.

[0013] The system may also include an intensity monitoring unit. Such an intensity monitoring unit includes a first photodiode for monitoring a first intensity of the first laser beam and a second photodiode for monitoring a second intensity of the modulated retroreflected laser beam. The intensity monitoring unit may also include a partial retro-reflector to provide a portion of the first laser beam to the first photodiode and a portion of the modulated retroreflected laser beam to the second photodiode. The system may also include an optical isolator and an input AOM. The optical isolator is between the input AOM and the chamber.

[0014] A system is described. The system includes an input AOM, an optical isolator, an optical modulation unit, and a retro-reflector. The optical isolator is optically coupled with the input AOM. A first laser beam optically coupled with a chamber is provided from the optical isolator. The chamber includes particles therein. The optical modulation unit is between the retro-reflector and the chamber. The optical modulation unit includes a first AOM and a second AOM. In some embodiments, the first AOM provides a first frequency shift and the second AOM provides a second frequency shift opposite to the first frequency shift. By varying the RF driving signal for the first and second AOMs, the intensity and phase of the retro reflected light can be varied. Thus, the optical modulation unit modulates at least one of intensity and phase. The optical modulation receives, at the first AOM, the first laser beam transmitted by the chamber and modulates the first laser beam to provide, from the second AOM, a second laser beam including a modulated first laser beam. The retro-reflector is optically coupled with the optical modulation unit and retroreflects the second laser beam toward the optical modulation unit in a counter-propagating direction. The optical modulation unit is configured to modulate the retroreflected laser beam to provide a modulated retroreflected laser beam. In some embodiments, the system is capable of providing a dipole trap and an optical lattice, as well as shaking the optical lattice.

[0015] The system may also include an intensity monitoring unit. The intensity monitoring unit includes a first photodiode for monitoring a first intensity of the first laser beam and a second photodiode for monitoring a second intensity of the retroreflected laser beam. In some embodiments, the system also includes an optical isolator and an input AOM. The optical isolator is between the input AOM and the chamber. In some embodiments, a single wedge inserted in the beam path may be used to pick off a small portion of the incoming and retroreflected light for stabilizing the intensity of each. The intensity of the light may be stabilized in a closed loop using the input AOM and either of the two AOMs in the retro-reflected path.

[0016] A method is described. The method includes receiving a first laser beam optically coupled with a chamber including particles (e.g. neutral atoms). The method also includes providing in the chamber at least one of an optical dipole trap for a first set of operating conditions of an optical modulation unit and an optical lattice for a second set of operating conditions of the optical modulation unit. The optical modulation unit is between a retro-reflector and the chamber. The optical dipole trap is formed by the first laser beam in the absence of a retroreflected laser beam within the chamber from the retro-reflector for the first set of operating conditions. The optical lattice is formed from the first laser beam and a modulated retroreflected laser beam from the optical modulation unit for the second set of operating conditions. The optical modulation unit modulating at least one of an intensity and a phase. In some embodiments, the method also includes phase and intensity modulating the retroreflected laser beam to shake the optical lattice.

[0017] For the second set of operating conditions, the optical modulation unit receives the first laser beam transmitted by the chamber and modulates the first laser beam to provide a second laser beam including a modulated first laser beam. The retro-reflector retroreflects the second laser beam toward the optical modulation unit in a counter-propagating direction. The optical modulation unit modulates the retroreflected laser beam to provide the modulated retroreflected laser beam to the chamber for the second set of operating conditions. The optical modulation unit may include a first AOM and a second AOM. The first AOM is between the chamber and the second AOM. In some such embodiments, the first AOM provides a first frequency shift and the second AOM provides a second frequency shift opposite to the first frequency shift. The method may also include intensity monitoring the first laser beam at a first photodiode and intensity monitoring the modulated retroreflected laser beam at a second photodiode. The method may also include isolating a laser source of the first laser beam from the modulated retroreflected beam using an optical isolator.

[0018] FIGS. 1A-1B are block diagrams depicting an embodiment of system 100 for forming a flexible, modulatable optical trap. System 100 includes chamber 130, optical modulation unit 120, and retro-reflector 110. Other and / or additional components may be present in some embodiments. FIG. 1A depicts system 100 in a first operating mode, where an optical lattice is formed in chamber 130. FIG. IB depicts system 100 in a second optical mode, where an optical dipole trap is formed in chamber 130.

[0019] Chamber 130 is configured to contain particles 132, such as neutral or charged atoms, molecules, or other small particles controllable using an optical trap. Further, chamber 130 is optically coupled with laser beam 140 that is provided by a laser (not explicitly shown in FIGS. 1A-1B) or other analogous source. Optical modulation unit 120 is between chamber 130 and retro-reflector 110. Optical modulation unit 120 is a phase and / or intensity modulator. Optical modulation unit 120 is configured to provide in chamber 130 an optical dipole trap for a first set of operating conditions and an optical lattice for a second set of operating conditions. Retro-reflector 110 is configured such that light (i.e. from laser beam 140) incident on retro reflector 110 is retroreflected, providing a counter-propagating laser beam 150.

[0020] In operation, laser beam 140 enters chamber 130 and travels toward optical modulation unit 120 and retro-reflector 110. Laser beam 140 is transmitted by chamber 130 and is incident on optical modulation unit 120. In the operating mode depicted in FIG. 1 A, optical modulation unit 120 prevents a retroreflected laser beam from being present in chamber 130. Thus, an optical dipole trap is formed in chamber 130 by laser beam 140. In some embodiments, optical modulation unit 120 does not transmit laser beam 140 to retro-reflector 110. In some embodiments, optical modulation unit 120 might not allow transmission of retroreflected laser beam 150 back to chamber 130. Optical modulation unit 120 may be viewed as modulating the intensity of laser beam 140 and / or 150 to be zero. Thus, a counter-propagating laser beam is not present in chamber 130 and an optical dipole trap rather than an optical lattice is formed in chamber 130 for the operating conditions corresponding to FIG. 1A.

[0021] For the operating conditions depicted in FIG. IB, optical modulation unit 120 allows counter-propagating beam 150 to be present in chamber 130. Thus, optical modulation unit 120 (phase and / or intensity) modulates and transmits modulated laser beam 140 toward retro-reflector 110. Laser beam 140 is retroreflected by retro-reflector 110, providing counterpropagating laser beam 150. Laser beam 150 travels from retro-reflector 110 toward optical modulation unit 120. Optical modulation unit 120 (phase and / or intensity) modulates and transmits the counter-propagating laser beam 150 toward chamber 130. Thus, laser beam 140 and counter-propagating laser beam 150 are present in chamber 130 and interfere. A standing wave may be formed in chamber 130 by laser beams 140 and 150. An optical lattice is, therefore, formed in chamber 130 for the operating conditions shown in FIG. IB. In some embodiments, optical modulation unit 120 is configured to smoothly transition between the operation depicted in FIG. 1A and that of FIG. IB. For example, optical modulation unit 120 may be turned off in the situation depicted in FIG. 1A, and turned on with varying amounts of modulation for the situation depicted in FIG. IB.

[0022] Using system 100, a running wave optical dipole trap or an optical lattice may be formed in chamber 130. Further, optical modulation unit 120 may be configured such that system 100 may smoothly transition from providing a running wave optical dipole trap (in FIG 1 A) to a retro-reflected standing wave trap (optical lattice) (in FIG. IB). Thus, flexibility of system 100 is improved. The optical dipole trap and optical lattice are also formed with a single laser beam line provided via a single laser source (for laser beam 140) and retro-reflector 110 (for laser beam 150). Thus, system 100 may be more compact, more readily fabricated, more easily deployable, and consumes less power. For the situation depicted in FIG. IB, optical modulation unit 120 may be configured to phase and or intensity modulate the optical lattice formed in chamber 130. For example, optical modulation unit 120 may turn on and off the optical lattice as well as phase modulate retroreflected laser beam 150. System 100 thus allowed for shaken lattice interferometry using a single beam line (i.e. laser beam 140 and retro-reflected beam 150) in a compact package. For example, system 100 may be used for applications such as those described in U.S. Patent 11,397,085 entitled Shaken-Lattice Matter-Wave Gyro. Thus, flexibility, manufacturability, and deployability of system 100 may be improved.

[0023] FIG. 2 is a diagram depicting an embodiment of system 200 for forming a flexible, modulatable optical trap. System 200 is analogous to system 100. System 200 includes chamber 230, optical modulation unit 220, retro-reflector 210, laser beam 240, and retroreflected beam 250 (for at least some operating conditions) that are analogous to chamber 130, optical modulation unit 120, retro-reflector 110, laser beam 140, and retroreflected beam 150, respectively. System 200 also includes intensity monitoring unit 260, optical isolator 270, input optical fiber 280, and input modulator 290. Other and / or additional components may be present in some embodiments.

[0024] Input optical modulator 290 may be an acousto-optical modulator (AOM). Intensity monitoring unit 160 allows for the intensities of laser beam 240 and retroreflected laser beam 250 to be separately monitored. Intensity monitoring unit 250 includes photodiodes 262 and 264 as well as partial retro-reflector 268. Laser beam 240 is transmitted and reflected by partial retro-reflector 268. The reflected portion of laser beam 240 is provided to photodiode 264, which monitors intensity. The transmitted portion of laser beam 240 is provided to chamber 230. Similarly, retroreflected laser beam 250 (incident from chamber 230) is transmitted and reflected by partial retro-reflector 268. The reflected portion of laser beam 250 is provided to photodiode 262, which monitors intensity. Thus, the intensities of laser beams 240 and 250 may be individually monitored by intensity monitoring unit 260.

[0025] Optical modulation unit 220 includes optical modulators 222 and 224 as well as lens 229. Optical modulators 222 and 224 are each AOMs. Thus, input signals 226 and 228 to AOMs 222 and 224, respectively control modulation of AOMs 222 and 224, respectively. Each AOM 222 and 224 provides a frequency shift and a deflection. AOMs 222 and 224 are configured such that the frequency shift provided by AOM 222 is compensated for by the frequency shift provided by AOM 224, and vice versa. Similarly, the deflection provided by AOM 222 is compensated for by the deflection provided by AOM 224, and vice versa. AOM 222 is controlled by input signal 226, which may be in the radiofrequency range. Similarly, AOM 224 is controlled by input signal 228, which may be in the radiofrequency range. In addition input signals 226 and 228 may have a phase difference, <p(t). As a result, AOMs 222 and 224 may provide phase and / or intensity modulation.

[0026] In operation, laser beam 240 is input to AOM 290. AOM 290 may be used to control the laser power input to system 200. Optical fiber 280 carries laser beam 240 from AOM 290 to optical isolator 270. Optical isolator 270 aids in preventing retroreflected beam 250 from being carried back to the input laser source. Laser beam 240 is transmitted to intensity monitor 260. A portion of laser beam 240 is tapped by partial retro-reflector 268 and provided to photodiode 264 for monitoring. Laser beam 240 is provided to chamber 230, in which a running wave optical dipole trap or optical lattice may be formed.

[0027] Laser beam 240 is transmitted to optical modulation unit 220. AOM 222 modulates laser beam 240, as well as frequency shifting and deflecting the beam. AOM 224 modulates and provides complementary frequency shifts and deflections for the laser beam from AOM 222. Lens 229 focuses the light and provides the laser beam to retro-reflector 210, which retroreflects the beam. The retroreflected, counter-propagating beam 250 is provided to AOM 222. AOM 222 modulates laser beam 250, as well as frequency shifting and deflecting the beam. AOM 222 modulates and provides complementary frequency shifts and deflections for the laser beam from AOM 224. This modulated, retroreflected beam is provided to chamber 230. Laser beams 240 and 250 form a standing wave in chamber 230. Thus, an optical lattice is formed. Retroreflected, counter-propagating beam 250 is transmitted by chamber 230 to intensity monitor 260. A portion of laser beam 250 is tapped by partial retro-reflector 268 and provided to photodiode 262 for monitoring. Isolated 270 prevents counter-propagating laser beam 250 from reaching the laser source (not shown).

[0028] Thus, an optical lattice may be formed in chamber 230. Further, the use of a phase change, here induced by AOM 224, may be used to change the phase of retroreflected laser beam 250 from that of laser beam 240. Moreover, AOMs 222 and 224 can intensity and phase modulate laser beams 240 and 250. Thus, the optical lattice formed in chamber 230 may be shaken. Characteristics of AOMs 222 and 224 may be otherwise tuned to provide other features of the optical lattice.

[0029] For a running wave optical dipole trap, AOM(s) 222 and 224 can be configured to turn off counter-propagating retroreflected beam 250. This may be achieved by shutting off input signals 226 and 228. By controlling input signals 226 and 228, system 200 may provide a running wave optical dipole trap and transition to an optical lattice.

[0030] System 200 shares the benefits of system 100. Thus, a flexible, compact system capable of providing a running wave optical dipole trap or an optical lattice. By driving AOMs 222 and 224 differentially, for example by attenuating or phase-shifting one of the two input RF signals 226 and 228, the optical lattice intensity and position can be modulated. A shaken optical lattice may be achieved. Further, these optical traps can be provided using a single beam line originating in one laser source. This may reduce the power consumed by system 200 over one which utilizes multiple laser sources. Use of AOMs 222 and 224 may allow for a reduction in cost and simple control over the type of trap provided as well as the characteristics of the trap. AOMs 222 and 224 allow for no net frequency shift, in contrast to a single local oscillator. Because of the use of a “cat’s eye” configuration for lens 229 and retro-reflector 210, system 200 is robust with respect to misalignments. Thus, flexibility, manufacturability, and deployability of system 200 may be improved.

[0031] FIG. 3 is a flow chart depicting an embodiment of method 300 for forming a flexible, modulatable optical trap. Method 300 is described in the context of particular steps in a given order. Other and / or additional steps as well as another order may be possible. Method 300 is described in the context of system 200. However, method 300 may be used with another system.

[0032] A laser beam is received by the system, at 302. The laser beam is optically coupled with a chamber including particles desired to be trapped. An optical dipole trap or an optical lattice are provided in the chamber using an optical modulation unit at 304. 304 includes using a first set of operating conditions of the n optical modulation unit if a running wave optical dipole trap is desired. 304 also includes using a second set of operating conditions for the optical modulation unit if the optical dipole trap is desired. The difference between the first and second set of conditions correspond to the use of a counter-propagating retroreflected beam in the chamber for the optical lattice and the absence of the counter-propagating retroreflected beam in the chamber if the optical dipole trap is desired. In some embodiments, the method also includes phase modulating the retroreflected laser beam to shake the optical lattice, at 306. In some embodiments, other changes to the optical modulation unit may be made at 306 to change the optical dipole trap or optical lattice in another manner.

[0033] Using method 300, the benefits of systems 100 and / or 200 may be achieved. For example, laser beam 240 may be received, at 302. AOMs 222 and 224 of optical modulation unit 220 are configured for the desired type of trap, at 304. This may be achieved via input signals 226 and 228. Thus, retroreflected laser beam 250 may be present or absent from chamber 230. For laser beam 240 and retroreflected laser beam 250 being present m chamber 230, an optical lattice is formed. For only laser beam 240 being present in chamber 230, an optical dipole trap is formed. If a shaken lattice is desired, then the phase and / or intensity of the retroreflected laser beam may be modulated via AOMs 222 and 224, at 306. Thus, the desired type of optical trap may be provided and controlled in a compact, flexible package.

[0034] FIG. 4 is a flow chart depicting an embodiment of method 400 for forming a flexible, modulatable optical trap. Method 400 is described in the context of particular steps in a given order. Other and / or additional steps as well as another order may be possible. Method 400 is described in the context of system 200. However, method 400 may be used with another system.

[0035] The operating conditions for the desired type of optical trap are set, at 402. Thus, the settings for the optical modulation unit may be configured to provide an optical dipole trap or an optical lattice. The laser beam is provided to the chamber, at 404. The laser beam may be from a single source. Because of the use of the described system, a single laser beam may be used for an optical dipole trap or an optical lattice. Thus, the desired type of trap is provided at 404. The operating conditions may be modified, at 406. The laser beam may also, again, be provided to the chamber. Thus, the type and / or properties of the optical trap provided can be changed.

[0036] Using method 400, the benefits of systems 100 and / or 200 may be achieved. For example, AOMs 222 and 224 of optical modulation unit 220 are configured for the desired type of trap, at 402. This may be achieved via input signals 226 and 228. Laser beam 240 may be provided to chamber 230, at 404. Because of the settings configured in 402, retroreflected laser beam 250 may be present or absent from chamber 230. For laser beam 240 and retroreflected laser beam 250 being present in chamber 230, an optical lattice is formed. For only laser beam 240 being present in chamber 230, an optical dipole trap is formed. Thus, the desired type of optical trap may be provided and controlled in a compact, flexible package. At 406, the operating conditions for optical modulation unit 220 may be modified. As a result, the properties and / or type of optical trap may be modified when the laser beam 240 is provided to chamber 230 at 404. Thus, the desired type of optical trap may be provided and controlled in a compact, flexible package.

[0037] Although the foregoing embodiments have been described in some detail for purposes of clarity of understanding, the invention is not limited to the details provided. There are many alternative ways of implementing the invention. The disclosed embodiments are illustrative and not restrictive.

[0038] The features disclosed in the foregoing description, or in the following claims, or in the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for obtaining the disclosed results, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

[0039] While the invention has been described in conjunction with the exemplary embodiments described above, many equivalent modifications and variations will be apparent to those skilled in the art when given this disclosure. Accordingly, the exemplary embodiments of the invention set forth above are considered to be illustrative and not limiting. Various changes to the described embodiments may be made without departing from the spirit and scope of the invention.

[0040] For the avoidance of any doubt, any theoretical explanations provided herein are provided for the purposes of improving the understanding of a reader. The inventors do not wish to be bound by any of these theoretical explanations.

[0041] Any section headings used herein are for organizational purposes only and are not to be construed as limiting the subject matter described.

[0042] Throughout this specification, including the claims which follow, unless the context requires otherwise, the word “comprise” and “include”, and variations such as “comprises”, “comprising”, and “including” will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

[0043] It must be noted that, as used in the specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from “about” one particular value, and / or to “about” another particular value. When such a range is expressed, another embodiment includes from the one particular value and / or to the other particular value. Similarly, when values are expressed as approximations, by the use of the antecedent “about,” it will be understood that the particular value forms another embodiment. The term “about” in relation to a numerical value is optional and means for example + / - 10%.

Claims

1. A system, comprising:a first laser beam optically coupled with a chamber including a plurality of particles;a retro-reflector; andan optical modulation unit between the retro-reflector and the chamber, the optical modulation unit being configured to provide in the chamber an optical dipole trap for a first set of operating conditions and an optical lattice for a second set of operating conditions, the optical dipole trap being formed by the first laser beam in an absence of a retroreflected laser beam from the retro-reflector, the optical lattice being formed from the first laser beam and a modulated retroreflected laser beam from the optical modulation unit, the optical modulation unit modulating at least one of an intensity and a phase.

2. The system of claim 1, wherein the optical modulation unit is configured to receive the first laser beam transmitted by the chamber and to modulate the first laser beam to provide a second laser beam including a modulated first laser beam for the second set of operating conditions; andwherein the retro-reflector retroreflects the second laser beam toward the optical modulation unit in a counter-propagating direction, the optical modulation unit being configured to modulate the retroreflected laser beam to provide the modulated retroreflected laser beam to the chamber for the second set of operating conditions.

3. The system of any preceding claim, wherein the optical modulation unit further includes: a first acousto-optical modulator (AOM); anda second AOM, the first AOM being between the chamber and the second AOM.

4. The system of claim 3, wherein the first AOM provides a first frequency shift and the second AOM provides a second frequency shift opposite to the first frequency shift.

5. The system of any preceding claim, further comprising:an intensity monitoring unit including a first photodiode for monitoring a first intensity of the first laser beam and a second photodiode for monitoring a second intensity of the modulated retroreflected laser beam.

6. The system of any preceding claim, further comprising:an optical isolator; andan input AOM, the optical isolator being between the input AOM and the chamber.

7. The system of any preceding claim, wherein the optical modulation unit is configured to phase modulate the retroreflected laser beam to shake the optical lattice.

8. A system, comprising:an input acousto-optical modulator (AOM);an optical isolator optically coupled with the input AOM, a first laser beam optically coupled with a chamber including a plurality of particles being provided from the optical isolator;an optical modulation unit including a first AOM and a second AOM, the optical modulation unit being configured to receive, at the first AOM, the first laser beam transmitted by the chamber and to modulate the first laser beam to provide, from the second AOM, a second laser beam including a modulated first laser beam, the optical modulation unit modulating at least one of an intensity and a phase; anda retro-reflector optically coupled with the optical modulation unit and retroreflecting the second laser beam toward the optical modulation unit in a counter-propagating direction from the second laser beam, the optical modulation unit being configured to modulate the retroreflected laser beam to provide a modulated retroreflected laser beam;wherein the optical modulation unit is between the retro-reflector and the chamber.

9. The system of claim 8, wherein the first AOM provides a first frequency shift and the second AOM provides a second frequency shift opposite to the first frequency shift.

10. The system of any of claims 8 to 9, further comprising:an intensity monitoring unit including a first photodiode for monitoring a first intensity of the first laser beam and a second photodiode for monitoring a second intensity of the retroreflected laser beam.

11. The system of any of claims 8 to 10, further comprising:an optical isolator; andan input AOM, the optical isolator being between the input AOM and the chamber.

12. A method, comprising:receiving a first laser beam optically coupled with a chamber including a plurality of particles;providing in the chamber at least one of an optical dipole trap for a first set of operating conditions of an optical modulation unit and an optical lattice for a second set of operating conditions of the optical modulation unit, the optical modulation unit being between a retroreflector and the chamber, the optical dipole trap being formed by the first laser beam in an absence of a retroreflected laser beam from the retro-reflector for the first set of operating conditions, the optical lattice being formed from the first laser beam and a modulated retroreflected laser beam from the optical modulation unit for the second set of operating conditions, the optical modulation unit modulating at least one of an intensity and a phase.

13. The method of claim 12, further comprising:phase modulating the retroreflected laser beam to shake the optical lattice.

14. The method of any of claims 12 to 13, wherein the optical modulation unit is configured to receive the first laser beam transmitted by the chamber and to modulate the first laser beam to provide a second laser beam including a modulated first laser beam for the second set of operating conditions; andwherein the retro-reflector is configured to retroreflect the second laser beam toward the optical modulation unit in a counter-propagating direction from the second laser beam, the optical modulation unit being configured to modulate the retroreflected laser beam to provide the modulated retroreflected laser beam to the chamber for the second set of operating conditions.

15. The method of any of claims 12 to 14, wherein the optical modulation unit includes a first acousto-optical modulator (AOM) and a second AOM, the first AOM being between the chamber and the second AOM.

16. The method of claim 15, wherein the first AOM provides a first frequency shift and the second AOM provides a second frequency shift opposite to the first frequency shift.

17. The method of any of claims 12 to 16, further comprising:intensity monitoring the first laser beam at a first photodiode; andintensity monitoring the modulated retroreflected laser beam at a second photodiode.

18. The method of any of claims 12 to 17, further comprising:isolating a laser source of the first laser beam from the modulated retroreflected beam using an optical isolator.

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