Device for in-situ tuning of light-induced dipole-dipole interactions between particles

Abstract

The present invention discloses a device for realizing in-situ tuning of light-induced dipole-dipole interaction between particles, comprising a light source module, a light trap modulation module, a vacuum chamber module, a detection module and a control module; the light source module provides a high-power laser for the light trap modulation module and provides a reference light for the detection module; the light trap modulation module is used to modulate the laser beam to generate a phase-coherent double beam; the vacuum chamber module provides a vacuum environment for optically suspended nanoparticles; the detection module realizes the detection of the movement of nanoparticles; the control module analyzes and processes the detection signal, inverts the interaction intensity of the particles and generates a control signal, controls the intensity modulator in the light trap modulation module to apply AC high-frequency modulation to the light beam, and uses feedback control to realize the control of the oscillation amplitude of two nanoparticles, thereby realizing in-situ tuning and control of light-induced dipole-dipole interaction between nanoparticles. The present invention can provide stable suspension of double nanoparticles under high vacuum.

Description

Technical Field

[0001] The invention belongs to the field of vacuum optical tweezers, and in particular relates to a device for realizing in-situ tuning of light-induced dipole-dipole interaction between particles. Background Art

[0002] Arthur Ashkin of the United States used light to capture microparticles in the 1970s. The device that uses light to capture and manipulate micro-nano particles is called optical tweezers. Optical tweezers technology has been widely used in many fields such as cell biology and physics.

[0003] Vacuum optical tweezers is a technology that uses optical tweezers to capture and manipulate particles in a vacuum environment. Highly focused lasers can be used to confine micro-nanoparticles in an optical potential well, and suspended micro-nanoparticles can be used as sensing units. Since the device has no mechanical connection, there is no mechanical dissipation. In addition, compared to optical tweezers using liquids or other media, vacuum optical tweezers achieve good isolation of the sensing unit from the external environment by virtue of their vacuum environment. They have the characteristics of low noise and high sensitivity and are widely used in basic physics, applied physics, precision measurement and other fields.

[0004] In recent years, related research has used vacuum optical tweezers systems to cool the center of mass motion of nanoparticles to the quantum ground state at room temperature. This has made the use of vacuum optical tweezers systems to study multi-body dynamics and macroscopic quantum effects a research hotspot. Dual-beam vacuum optical tweezers is a system that uses dual optical traps to suspend two micro-nanoparticles in a vacuum environment. This system combines vacuum optical tweezers and light field control technology to tune the interaction between micro-nanoparticles in situ, becoming an important system for observing macroscopic quantum entanglement and studying two-body dynamics at room temperature.

[0005] For the dual-beam vacuum optical tweezers system, the coupling interaction between micro-nanoparticles is the key to achieving two-body entanglement and studying two-body dynamics. Currently, it is mainly divided into electrostatic interaction and light-induced dipole-dipole interaction. Compared with the former, regulating the light-induced dipole-dipole interaction does not require the microspheres to be charged, but only requires controlling the polarization, amplitude and phase of the captured light field, so it has the characteristics of easy operation and in-situ.

[0006] Phase coherence of the optical trap is the prerequisite for the generation of light-induced dipole-dipole interactions between particles. There is interaction between the suspended nanoparticles in the phase-coherent double optical trap, and the effect of the i-th particle on the j-th particle g ij It can be expressed as:

[0007] g 12 =(k1+k2)( q2-q1)

[0008] g 21 =(k1-k2)( q1-q2)

[0009] In the formula, q i represents the displacement of the ith microsphere, and the interaction g ij It consists of a reciprocal term k1 and a non-reciprocal term k2. The existing methods used to adjust the coupling interaction are to change the phase, spacing, polarization of the light trap, or to emphasize the light to a certain value, thereby changing k1 and k2. The disadvantage of these methods is that due to the existence of non-conservative forces, the movement of particles will be amplified by resonance, causing the system to be unstable and particles to escape easily. In addition, the system parameters drift, resulting in the instability of the interaction. Summary of the invention

[0010] In view of the deficiencies of the prior art, the present invention proposes a device for in-situ tuning of light-induced dipole-dipole interactions between particles, by applying a certain amplitude of AC high-frequency modulation to the original light trap intensity, and by feedback control to achieve amplitude locking of the particle coupling mode, thereby achieving in-situ tuning and locking of the coupling interaction. That is, in-situ tuning and locking of the coupling interaction between microspheres is achieved by controlling the amplitude of the microspheres. Because the essence of the device and method of the present invention is amplitude locking, the amplification of the particle motion by the non-conservative term k2 can be avoided, and thus the instability caused by the particle resonance can be avoided. At the same time, the introduction of the feedback system can help detect the interaction intensity in real time and achieve stable control and locking thereof.

[0011] The purpose of the present invention is achieved through the following technical solutions:

[0012] A device for realizing in-situ tuning of light-induced dipole-dipole interaction between particles, comprising a light source module, a light trap modulation module, a vacuum chamber module, a detection module and a control module;

[0013] The light source module provides high-power laser light to the light trap modulation module and provides reference light to the detection module at the same time;

[0014] The light trap modulation module is used to modulate the laser light beam generated by the light source module to generate a phase-coherent double light beam;

[0015] The vacuum chamber module is used to provide a vacuum environment for the two optically suspended nanoparticles, and to tightly focus the double light beams generated by the optical trap modulation module to form a double optical trap, so as to capture the two nanoparticles and collect the forward signal light of the two nanoparticles;

[0016] The detection module separates and detects the forward signal lights of the two nanoparticles by using the orthogonal polarization characteristics, and inputs the detected differential signal into the control module;

[0017] The control module is used to analyze and process the detected differential signal to obtain the signal power spectrum, from which the motion information of each nanoparticle is obtained, and a phase-locked loop is used to generate a signal synchronized with the frequency and phase of the movement of the nanoparticle, generate the double frequency of the signal, and superimpose a compensation phase to match the delay of the loop; finally, the processed signal is used as a control signal for the movement of the particle and fed back to the light trap modulation module, which modulates the light intensity of the captured light, thereby realizing the regulation of the movement amplitude of the double nanoparticles.

[0018] Further, the light source module includes a laser, a first half-wave plate, a first polarization beam splitter prism, a first reflector, a second half-wave plate, a second polarization beam splitter prism, and a second reflector;

[0019] The laser is used to generate low-noise, high-power and high-stability laser light. The emitted laser passes through the first half-wave plate and the first polarization beam splitter prism in sequence and is divided into transmitted light and reflected light; wherein the transmitted light enters the light trap modulation module; the reflected light is reflected by the first reflector, and then passes through the second half-wave plate and the second polarization beam splitter prism in sequence and is divided into two beams. The two beams of light are input into the detection module and are respectively used as reference lights for detecting two nanoparticle signals.

[0020] Further, the light trap modulation module includes a light intensity modulator, a first lens, a second lens, a third reflector, a third half-wave plate, a spatial light modulator, a fourth reflector, a fourth half-wave plate, a third lens, and a fourth lens, which are sequentially arranged along the light path;

[0021] The light intensity modulator is electrically connected to the control module, and is used to receive the control signal of the control module and modulate the light intensity of the incident laser light beam; the first lens and the second lens form a beam expansion system to expand the laser light beam; the third reflector is used to reflect the expanded laser light to the third half-wave plate, and the third half-wave plate tilts the polarization of the incident light by 45° relative to the polarization sensitive direction of the spatial light modulator, and then the incident light enters the spatial light modulator, and the spatial light modulator loads a linear phase, so that the unmodulated light and the modulated light form a double light beam with mutually perpendicular polarizations; after the double light beams are reflected by the fourth reflector, the polarization of the double light beams is adjusted by the fourth half-wave plate, and then the double light beams pass through the 4f system composed of the third lens and the fourth lens, and the light path is extended and aligned, and then the double light beams are injected into the vacuum cavity module behind the light path.

[0022] Further, the vacuum chamber module includes a vacuum chamber, and a tightly focused light trap generating element and a collecting lens located inside the vacuum chamber;

[0023] The tightly focused light trap generating element tightly focuses the double light beams generated by the light trap modulation module to form a double light trap that captures two nanoparticles simultaneously; the collecting lens is used to collect and collimate the forward signal light of the two nanoparticles and input it into the detection module at the rear.

[0024] Furthermore, the detection module includes a fifth half-wave plate, a third polarization beam splitter prism and a differential detector. The fifth half-wave plate and the third polarization beam splitter prism are used to separate particle motion signals; and the differential detector is used to detect the motion of two particles.

[0025] Furthermore, the control module is a signal processing system, which is used to analyze and process the electrical signal output by the detection module, generate a control signal, and input it into the light trap modulation module to modulate the laser power, thereby modulating the light trap stiffness, thereby locking the motion amplitude of the nanoparticles, and further realizing in-situ tuning of the light-induced dipole-dipole interaction between nanoparticles.

[0026] Furthermore, the light intensity modulator is an acousto-optic modulator and an optical trash can arranged in sequence along the optical path, the acousto-optic modulator is used to diffract the laser beam entering the light trap modulation module, the diffracted light is collected by the optical trash can, and the 0-order light enters the first lens and the second lens to form a beam expansion system to achieve beam expansion;

[0027] Alternatively, the light intensity modulator includes a first polarizer, an electro-optic modulator and a second polarizer which are sequentially arranged along the light path.

[0028] Furthermore, the spatial light modulator is composed of a right-angle reflection prism and a reflective spatial light modulator, or the spatial light modulator is a transmissive spatial light modulator.

[0029] Furthermore, the differential detector is two independent four-quadrant detectors, or a combination of a D-type mirror and a balanced detector.

[0030] A method for realizing in-situ tuning of light-induced dipole-dipole interaction between particles, the method is realized based on a device for realizing in-situ tuning of light-induced dipole-dipole interaction between particles, the method comprising:

[0031] The laser beam generated by the light source module enters the light trap modulation module, and the light trap modulation module modulates the laser beam to generate a phase-coherent double beam; the double beam enters the vacuum chamber module and is gathered to form a double light trap, and the double light trap is used to capture two nanoparticles, and the two nanoparticles are placed in a vacuum environment and their forward signal light is collected; the forward signal light of the two nanoparticles is separated and detected by the detection module, and the detected differential signal is input into the control module;

[0032] The control module is used to analyze and process the detected differential signal to obtain a signal power spectrum, from which the motion information of each nanoparticle is obtained, and a phase-locked loop is used to generate a signal synchronized with the frequency and phase of the movement of the nanoparticle, generate the double frequency of the signal, and superimpose a compensation phase to match the delay of the loop; finally, the processed signal is used as a control signal for the movement of the particle and fed back to the light trap modulation module, which modulates the light intensity of the captured light, thereby realizing the regulation of the movement amplitude of the double nanoparticles.

[0033] The beneficial effects of the present invention are as follows:

[0034] The method of the present invention adopts amplitude locking technology to achieve in-situ tuning and control of the interaction between particles. Compared with the existing resonance instability introduced by non-conservative interactions caused by adjusting the phase, spacing, polarization and intensity parameters of the light trap, the method of the present invention can provide stable suspension of double nanoparticles under high vacuum, avoiding the instability of interaction changes caused by drift of various parameters, and providing a basis for related research under higher vacuum. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are only examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims.

[0036] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities may be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0037] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0038] Figure 1 Schematic diagram of light-induced dipole-dipole interactions between optically suspended nanoparticles.

[0039] Figure 2 This is a diagram showing the relationship between the particle movement position and the change in the optical potential well.

[0040] Figure 3Schematic diagram of the composition of a device for achieving in-situ tuning of light-induced dipole-dipole interaction between particles according to an embodiment of the present invention.

[0041] Figure 4 FIG. 1 is a schematic diagram of a device for achieving in-situ tuning of light-induced dipole-dipole interactions between particles according to one embodiment of the present invention.

[0042] Figure 5 FIG. 4 is a schematic diagram of a light trap modulation module according to another embodiment of the present invention.

[0043] In the figure, light source module 1, light trap modulation module 2, vacuum chamber module 3, detection module 4, control module 5, laser 101, first half-wave plate 102, first polarization beam splitter prism 103, first reflector 104, second half-wave plate 105, second polarization beam splitter prism 106, second reflector 107, acousto-optic modulator 201, optical trash can 202, first lens 203, second lens 204, third reflector 205, third half-wave plate 206, right-angle reflection prism 207, spatial light modulator 2 08, fourth reflector 209, fourth half-wave plate 210, third lens 211, fourth lens 212, first polarizer 213, electro-optic modulator 214, second polarizer 215, transmissive spatial light modulator 216, vacuum chamber 301, tightly focused light trap generating element 302, captured nanoparticles 303, collecting lens 304, fifth half-wave plate 401, third polarization beam splitter prism 402, first signal collector 403, second signal collector 404, signal processing system 501. DETAILED DESCRIPTION

[0044] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0045] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0046] It should be understood that although the terms first, second, third, etc. may be used in the present application to describe various information, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0047] It should also be noted that the "multiple" mentioned in this application refers to two or more than two. "And / or" describes the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship.

[0048] The present invention applies high-frequency modulation to the intensity of the captured light, thereby achieving modulation of the light trap stiffness, so that the motion amplitude of the particle coupling mode can be cooled, and amplitude locking is achieved through feedback control, thereby realizing in-situ tuning of the coupled interaction, providing a new method for solving the in-situ tuning of the interaction between microspheres, and helping to promote the application of dual-beam vacuum optical tweezers in basic physics research fields such as two-body dynamics and macroscopic quantum entanglement.

[0049] Light-induced dipole-dipole interactions between optically suspended nanoparticles Figure 1 As shown in the figure, the tightly focused optical trap forms a trapping potential, and the two trapped nanoparticles can be regarded as having resonance frequencies of and The coefficient of action of the i-th particle on the j-th particle is g ij .

[0050] like Figure 2 As shown, the nanoparticles reciprocate in the optical potential trap, and the potential energy and mechanical energy of the nanoparticles are converted into each other. By adjusting the intensity of the captured light, the stiffness of the optical trap can be adjusted, thereby achieving the regulation of the amplitude of the particle movement. Since the nanoparticles move periodically, the modulation of the intensity of the captured light is also AC modulation. When the modulation frequency of the intensity of the captured light is twice the frequency of the particle movement, the amplitude of the particle can be effectively regulated. Therefore, applying a small high-frequency AC modulation to the intensity of the captured light can achieve the regulation of the particle movement amplitude without changing the mean value of the light intensity at the optical trap.

[0051] like Figure 3 As shown, a device for realizing in-situ tuning of light-induced dipole-dipole interaction between particles according to one embodiment of the present invention comprises a light source module 1, a light trap modulation module 2, a vacuum chamber module 3, a detection module 4, and a control module 5.

[0052] The light source module 1 provides high-power laser light to the light trap modulation module 2 and provides reference light to the detection module 4 at the same time.

[0053] The light trap modulation module 2 is used to modulate the laser light beam generated by the light source module 1 to generate phase-coherent dual light beams.

[0054] The vacuum chamber module 3 is used to provide a vacuum environment for optically suspending two nanoparticles, and to tightly focus the double light beams generated by the light trap modulation module 2 to form a double light trap, to capture the two nanoparticles, and to collect the forward signal light of the two nanoparticles;

[0055] The detection module 4 uses the orthogonal polarization characteristics to separate and detect the forward signal lights of the two nanoparticles, and inputs the detected differential signal into the control module 5;

[0056] The control module 5 is used to analyze and process the detected differential signal to obtain the signal power spectrum, from which the motion information of each nanoparticle is obtained, and a phase-locked loop is used to generate a signal synchronized with the frequency and phase of the movement of the nanoparticle, generate the double frequency of the signal, and superimpose a compensation phase to match the delay of the loop; finally, the processed signal is used as a control signal for the movement of the particle and fed back to the light trap modulation module 2, which modulates the intensity of the captured light, thereby realizing the regulation of the movement amplitude of the double nanoparticles.

[0057] Figure 4 A specific application example of the device for realizing in-situ tuning of light-induced dipole-dipole interaction between particles of the present invention is given, the device comprises a light source module 1 composed of a laser 101, a first half-wave plate 102, a first polarization beam splitter prism 103, a first reflector 104, a second half-wave plate 105, a second polarization beam splitter prism 106, and a second reflector 107, and an acousto-optic modulator 201, an optical trash can 202, a first lens 203, a second lens 204, a third reflector 205, a third half-wave plate 206, a straight A light trap modulation module 2 composed of a corner reflection prism 207, a spatial light modulator 208, a fourth reflection mirror 209, a fourth half-wave plate 210, a third lens 211, and a fourth lens 212; a vacuum cavity module 3 composed of a vacuum cavity 301, a tightly focused light trap generating element 302, and a collecting lens 304; a detection module 4 composed of a fifth half-wave plate 401, a third polarization splitter prism 402, a first signal collector 403, and a second signal collector 404; and a control module 5 composed of a signal processing system 501.

[0058] Among them, the laser 101 generates a low-noise, high-power and high-stability laser with a wavelength of 1064nm. The emitted laser passes through the first half-wave plate 102 and the first polarization beam splitter prism 103 and is divided into two parts. The transmitted light enters the light trap modulation module 2, and the reflected light passes through the first reflector 104 and then passes through the second half-wave plate 105 and the second polarization beam splitter prism to be divided into two beams, and input into the detection module 4 as reference lights for detecting two nano-particle signals respectively.

[0059] The laser beam entering the light trap modulation module 2 is diffracted by the acousto-optic modulator 201, and the diffracted light is collected by the optical trash can 202. The 0-order light is expanded by the beam expansion system composed of the first lens 203 and the second lens 204. After being reflected by the third reflector 205, it passes through the third half-wave plate 206, and then after being reflected by a right-angle reflection edge of a right-angle reflection prism 207, the light is irradiated on the reflective spatial light modulator 208 at a small angle. After being phase modulated, the reflected light is reflected again by another right-angle reflection edge of the right-angle reflection prism 209. Utilizing the polarization-sensitive characteristic of the reflective spatial light modulator 208, the third half-wave plate 206 tilts the polarization of the incident light by 45° relative to the polarization-sensitive direction of the reflective spatial light modulator 208, and then loads a linear phase on the reflective spatial light modulator 208, so that the unmodulated light and the modulated light form a double light trap with mutually perpendicular polarizations. After passing through the fourth reflector 209, the reflected light beam passes through a fourth half-wave plate 210 for adjusting the polarization of the dual light beams, and then passes through a 4f system composed of a third lens 211 and a fourth lens 212 to extend and align the light path and inject into the vacuum chamber module 3 at the rear.

[0060] The vacuum cavity 301 can withstand a high vacuum of 1e-8mbar, and the cavity mirror thereon is coated with a 1064nm anti-reflection film. After the captured light beam passes through the tight focusing light trap generating element 302, a double light trap that can capture two nanoparticles 303 at the same time is formed. The tight focusing light trap generating element in this embodiment is a microscope objective lens with a numerical aperture of 0.8, and other elements can also be used to replace the microscope objective lens, such as a single lens with a high numerical aperture. Afterwards, the forward signal light is collected and collimated by the collecting lens 304 and then output outside the vacuum cavity and input into the detection module 4 at the rear. A vacuum gauge interface and a vacuum pump group interface are also provided on the vacuum cavity 301. The vacuum gauge interface is connected to the vacuum gauge to monitor the vacuum degree in the cavity in real time. The vacuum pump group interface is connected to the vacuum pump group through a vacuum valve, which is used to evacuate and provide a vacuum environment for the optically suspended nanoparticles.

[0061] The detection module 4 uses the orthogonal polarization characteristics to separate the motion signals of the two nanoparticles and complete independent detection. The signal light collected and collimated by the collection lens 304 passes through the fifth half-wave plate 401 and the third polarization beam splitter prism 402 to complete the separation of the particle motion signal, and then is collected by the first signal collector 403 and the second signal collector 404 respectively, and is converted into electrical signals and analyzed. The first signal collector 403 and the second signal collector 404 each include a four-quadrant detector, which can realize particle motion detection.

[0062] The electrical signals output by the first signal collector 403 and the second signal collector 404 enter the control module 5, are analyzed and processed by the signal processing system 501, generate control signals and input them into the acousto-optic modulator 201 in the light trap modulation module 2, drive the acousto-optic modulator 201 to modulate the light intensity of the captured light, thereby locking the amplitude of the motion of the nanoparticles, and further realizing the in-situ tuning of the light-induced dipole-dipole interaction between the nanoparticles.

[0063] The present invention also provides another embodiment, in which the light intensity modulator composed of the acousto-optic modulator 201 and the optical trash can 202 is replaced by the first polarizer 213, the electro-optic modulator 214, and the second polarizer 215. The spatial light modulator composed of the right-angle reflection prism 207 and the reflective spatial light modulator 208 is replaced by the transmissive spatial light modulator 216. Figure 5 As shown, the light trap modulation module 2 in this embodiment includes a first polarizer 213, an electro-optical modulator 214, a second polarizer 215, a first lens 203, a second lens 204, a third reflector 205, a third half-wave plate 206, a transmissive spatial light modulator 216, a fourth reflector 209, a fourth half-wave plate 210, a third lens 211, and a fourth lens 212.

[0064] In addition, in the detection module 4, the differential detector composed of the first signal collector 403 and the second signal collector 404 is two independent four-quadrant detectors, and can also be a combination of a D-type mirror and a balanced detector to measure the motion signal of the particles captured by the optical tweezers system.

[0065] The present invention also provides an embodiment of a method for achieving in-situ tuning of light-induced dipole-dipole interactions between particles, the method comprising:

[0066] The laser beam generated by the light source module 1 enters the light trap modulation module 2, which modulates the laser beam to generate a phase-coherent double beam; the double beams enter the vacuum chamber module 3 and are gathered to form a double light trap, which is used to capture two nanoparticles, and the two nanoparticles are placed in a vacuum environment and their forward signal light is collected; the forward signal light of the two nanoparticles is separated and detected by the detection module 4, and the detected differential signal is input into the control module 5;

[0067] The detected differential signal is analyzed and processed by the control module 5 to obtain the signal power spectrum, from which the motion information of each nanoparticle is obtained, and a phase-locked loop is used to generate a signal synchronized with the frequency and phase of the movement of the nanoparticle, generate the double frequency of the signal, and superimpose a compensation phase to match the delay of the loop; finally, the processed signal is used as a control signal for the movement of the particle and fed back to the light trap modulation module 2, which modulates the light intensity of the capture light, thereby realizing the regulation of the movement amplitude of the double nanoparticles.

[0068] The present invention can solve the problem that the light-induced dipole-dipole interaction between nanoparticles in the field of double-beam vacuum optical tweezers cannot be tuned in situ, realizes precise control of nonlinear effects in the double-beam vacuum optical tweezers system, and provides means for in situ tuning of two-body coupling interaction.

[0069] The invention is applicable to a system for studying light-induced dipole-dipole interactions between particles, and is also applicable to an experimental system for performing two-body dynamics simulation and macroscopic quantum entanglement using a related platform.

[0070] Those skilled in the art will readily appreciate other embodiments of the present application after considering the description and practicing the contents disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The description and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the claims.

[0071] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A device for in-situ tuning of light-induced dipole-dipole interactions between particles, characterized in that: It comprises a light source module (1), a light trap modulation module (2), a vacuum chamber module (3), a detection module (4) and a control module (5); The light source module (1) provides high-power laser light to the light trap modulation module (2) and provides reference light to the detection module (4); The light trap modulation module (2) is used to modulate the laser light beam generated by the light source module (1) to generate phase-coherent dual light beams; The vacuum chamber module (3) is used to provide a vacuum environment for optically suspending two nanoparticles, and to tightly focus the double light beams generated by the light trap modulation module (2) to form a double light trap, so as to capture the two nanoparticles and collect the forward signal light of the two nanoparticles; The detection module (4) uses orthogonal polarization characteristics to separate and detect the forward signal lights of the two nanoparticles, and inputs the detected differential signal into the control module (5); The control module (5) is used to analyze and process the detected differential signal to obtain a signal power spectrum, from which the motion information of each nanoparticle is obtained, and a phase-locked loop is used to generate a signal synchronized with the frequency and phase of the movement of the nanoparticle, generate a double frequency of the signal, and superimpose a compensation phase to match the delay of the loop; finally, the processed signal is used as a control signal for the movement of the particle and fed back to the light trap modulation module (2), and the light trap modulation module (2) modulates the light intensity of the capture light, thereby realizing the regulation of the movement amplitude of the double nanoparticles; The control module (5) is a signal processing system, which is used to analyze and process the electrical signal output by the detection module (4), generate a control signal, and input the control signal into the light trap modulation module (2), modulate the laser power, thereby modulating the light trap stiffness, and achieving locking of the motion amplitude of the nanoparticles, thereby achieving in-situ tuning of the light-induced dipole-dipole interaction between the nanoparticles.

2. The device for realizing in-situ tuning of light-induced dipole-dipole interaction between particles according to claim 1, characterized in that: The light source module (1) comprises a laser (101), a first half-wave plate (102), a first polarization beam splitter prism (103), a first reflector (104), a second half-wave plate (105), a second polarization beam splitter prism (106), and a second reflector (107); The laser (101) is used to generate low-noise, high-power and high-stability laser light. The emitted laser light passes through the first half-wave plate (102) and the first polarization beam splitter prism (103) in sequence and is divided into transmitted light and reflected light. The transmitted light enters the light trap modulation module (2). The reflected light is reflected by the first reflector (104) and then passes through the second half-wave plate (105) and the second polarization beam splitter prism (106) in sequence and is divided into two beams. The two beams are input into the detection module (4) and are respectively used as reference lights for detecting two nanoparticle signals.

3. The device for realizing in-situ tuning of light-induced dipole-dipole interaction between particles according to claim 1, characterized in that: The light trap modulation module (2) comprises a light intensity modulator, a first lens (203), a second lens (204), a third reflector (205), a third half-wave plate (206), a spatial light modulator, a fourth reflector (209), a fourth half-wave plate (210), a third lens (211), and a fourth lens (212) which are sequentially arranged along the light path; The light intensity modulator is electrically connected to the control module (5) and is used to receive a control signal from the control module (5) and modulate the light intensity of the incident laser light beam; the first lens (203) and the second lens (204) form a beam expansion system to expand the laser light beam; the third reflector (205) is used to reflect the expanded laser light to the third half-wave plate (206); the third half-wave plate (206) tilts the polarization of the incident light by 45° relative to the polarization sensitive direction of the spatial light modulator, and then the incident light enters the spatial light modulator; the spatial light modulator loads a linear phase, so that the unmodulated light and the modulated light form a double beam with mutually perpendicular polarizations; After the double light beam is reflected by the fourth reflector (209), the polarization of the double light beam is adjusted by the fourth half-wave plate (210), and then the double light beam passes through the 4f system composed of the third lens (211) and the fourth lens (212) to extend and align the light path, and then is injected into the vacuum cavity module (3) behind the light path.

4. The device for realizing in-situ tuning of light-induced dipole-dipole interaction between particles according to claim 1, characterized in that: The vacuum chamber module (3) comprises a vacuum chamber (301), and a tight focusing light trap generating element (302) and a collecting lens (304) located inside the vacuum chamber (301); The tightly focused light trap generating element (302) tightly focuses the double light beams generated by the light trap modulation module (2) to form a double light trap that captures two nanoparticles simultaneously; the collecting lens (304) is used to collect and collimate the forward signal light of the two nanoparticles and input it into the detection module (4) at the rear.

5. The device for realizing in-situ tuning of light-induced dipole-dipole interaction between particles according to claim 1, characterized in that: The detection module (4) comprises a fifth half-wave plate (401), a third polarization beam splitter prism (402) and a differential detector; the fifth half-wave plate (401) and the third polarization beam splitter prism (402) are used to separate particle motion signals; and the differential detector is used to detect the motion of two particles.

6. The device for realizing in-situ tuning of light-induced dipole-dipole interaction between particles according to claim 3, characterized in that: The optical intensity modulator is an acousto-optic modulator (201) and an optical trash can (202) arranged in sequence along the optical path, the acousto-optic modulator (201) is used to diffract the laser beam entering the optical trap modulation module (2), the diffracted light is collected by the optical trash can (202), and the zero-order light enters the beam expansion system composed of the first lens (203) and the second lens (204) to achieve beam expansion; Alternatively, the light intensity modulator comprises a first polarizer (213), an electro-optic modulator (214), and a second polarizer (215) which are sequentially arranged along the light path.

7. The device for realizing in-situ tuning of light-induced dipole-dipole interaction between particles according to claim 3, characterized in that: The spatial light modulator is composed of a right-angle reflection prism (207) and a reflective spatial light modulator (208), or the spatial light modulator is a transmissive spatial light modulator (216).

8. The device for realizing in-situ tuning of light-induced dipole-dipole interaction between particles according to claim 5, characterized in that: The differential detector is two independent four-quadrant detectors, or a combination of a D-type mirror and a balanced detector.

9. A method for in-situ tuning of light-induced dipole-dipole interactions between particles, characterized in that: The method is implemented based on the device for in-situ tuning of light-induced dipole-dipole interactions between particles according to claim 1, and the method comprises: The laser beam generated by the light source module (1) enters the light trap modulation module (2), and the light trap modulation module (2) modulates the laser beam to generate a phase-coherent double beam; the double beam enters the vacuum chamber module (3) and is gathered to form a double light trap, and the double light trap is used to capture two nanoparticles, and the two nanoparticles are placed in a vacuum environment and their forward signal light is collected; the forward signal light of the two nanoparticles is separated and detected by the detection module (4), and the detected differential signal is input into the control module (5); The control module (5) analyzes and processes the detected differential signal to obtain a signal power spectrum, from which the motion information of each nanoparticle is obtained, and a phase-locked loop is used to generate a signal synchronized with the frequency and phase of the motion of the nanoparticle, generating a double frequency of the signal, and superimposing a compensation phase to match the delay of the loop; finally, the processed signal is used as a control signal for the motion of the particle and fed back to the light trap modulation module (2), and the light trap modulation module (2) modulates the light intensity of the captured light to achieve locking of the motion amplitude of the nanoparticle, thereby achieving in-situ tuning of the light-induced dipole-dipole interaction between the nanoparticles.

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