The fringe noises disrupt the precise measurement of the atom distribution in the process of the absorption images.The fringe removal algorithms have been proposed to reconstruct the ideal reference images of the abso...The fringe noises disrupt the precise measurement of the atom distribution in the process of the absorption images.The fringe removal algorithms have been proposed to reconstruct the ideal reference images of the absorption images to remove the fringe noises.However,the focus of these fringe removal algorithms is the association of the fringe removal performance with the physical systems,leaving the gap to analyze the workflows of different fringe removal algorithms.This survey reviews the fringe removal algorithms and classifies them into two categories:the imagedecomposition based methods and the deep-learning based methods.Then this survey draws the workflow details of two classical fringe removal algorithms,and conducts experiments on the abs DL ultracold image dataset.Experiments show that the singular value decomposition(SVD)method achieves outstanding performance,and the U-net method succeeds in implying the image inpainting idea.The main contribution of this survey is the interpretation of the fringe removal algorithms,which may help readers have a better understanding of the research status.展开更多
The nanomechanical resonator based on a levitated particle exhibits unique advantages in the development of ultrasensitive electric field detectors. We demonstrate a three-dimensional, high-sensitivity electric field ...The nanomechanical resonator based on a levitated particle exhibits unique advantages in the development of ultrasensitive electric field detectors. We demonstrate a three-dimensional, high-sensitivity electric field measurement technology using the optically levitated nanoparticle with known net charge. By scanning the relative position between nanoparticle and parallel electrodes, the three-dimensional electric field distribution with microscale resolution is obtained. The measured noise equivalent electric intensity with charges of 100e reaches the order of 1 μV·cm^(-1)·Hz^(-1/2)at 1.4 × 10^(-7) mbar. Linearity analysis near resonance frequency shows a measured linear range over 91 d B limited only by the maximum output voltage of the driving equipment. This work may provide an avenue for developing a high-sensitivity electric field sensor based on an optically levitated nano-resonator.展开更多
Sensing sensitivity is the key performance of optical tweezers.By adjusting the frequency and magnitude of an applied Coulomb force as an input of optical tweezers,we directly measured the sensitivity and signal-to-no...Sensing sensitivity is the key performance of optical tweezers.By adjusting the frequency and magnitude of an applied Coulomb force as an input of optical tweezers,we directly measured the sensitivity and signal-to-noise ratio(SNR)of a system and indirectly calculated the actual noise magnitude.Combined with an output filter,the relationship between the SNR and bandwidths was studied.We established the simulation model of a system using Simulink and simulated the relationship between the SNR and magnitude of the input forces and filter bandwidths.In addition,we built an experimental system to determine the relationship between the SNR and the magnitude of the input forces and filter bandwidths.The actual minimum detectable force was measured as 1.8275×10^(-17)N at a 1Hz bandwidth.The experimental results were correlated with the simulation and theoretical results,confirming the effectiveness of the proposed method and demonstrating the high sensitivity of vacuum optical tweezers as mechanical sensors.We proposed a novel method of calibration and measurement of system sensing parameters by applying an actual force that was more direct and precise than the theoretical calculation method that requires accurate fitting parameters,such as the particle radius and density.This method can be employed to analyze the system noise and phase characteristics to confirm and improve the real performance of the system.展开更多
Optical trap,a circularly polarized laser beam can levitate and control the rotation of microspheres in liquid medium with high stiffness.Trapping force performs as confinement while the trapped particle can be analog...Optical trap,a circularly polarized laser beam can levitate and control the rotation of microspheres in liquid medium with high stiffness.Trapping force performs as confinement while the trapped particle can be analog to a liquid floated gyroscope with three degree-of-ffeedom.In this work,we analyzed the feasibility of applying optically levitated rotor in the system.We presented the dynamic analysis and simulation of an ellipsoid micron particle.The precession motion and nutation motion of a rotating ellipsoid probe particle in optical tweezers were performed.We also analyzed the attitude changes of an optically levitated ellipsoid when there was variation of the external torque caused by deviation of the incident light that was provided.Furthermore,the trail path of the rotational axis vertex and the stabilization process of a particle of different ellipticities were simulated.We compared the movement tendencies of particles of different shapes and analyzed the selection criteria of ellipsoid rotor.These analytical formulae and simulation results are applicable to the analysis of the rotational motion of particles in optical tweezers,especially to the future research of the gyroscope effect.展开更多
In recent years,levitated particles of optical traps in vacuum have shown the enormous potential for precision sensor development and new physics exploration.However,the accuracy of the sensor is still hampered by the...In recent years,levitated particles of optical traps in vacuum have shown the enormous potential for precision sensor development and new physics exploration.However,the accuracy of the sensor is still hampered by the uncertainty of the calibration factor relating the detected signal to the absolute displacement of the trapped particle.In this paper,we suggest and experimentally demonstrate a novel calibration method for optical tweezers based on free-falling particles in vacuum,where the gravitational acceleration is introduced as an absolute reference.Our work provides a calibration protocol with a great certainty and traceability,which is significant in improving the accuracy of precision sensing based on levitated optomechanical systems.展开更多
基金founded by the National Natural Science Foundation of China(Grant No.62003020)。
文摘The fringe noises disrupt the precise measurement of the atom distribution in the process of the absorption images.The fringe removal algorithms have been proposed to reconstruct the ideal reference images of the absorption images to remove the fringe noises.However,the focus of these fringe removal algorithms is the association of the fringe removal performance with the physical systems,leaving the gap to analyze the workflows of different fringe removal algorithms.This survey reviews the fringe removal algorithms and classifies them into two categories:the imagedecomposition based methods and the deep-learning based methods.Then this survey draws the workflow details of two classical fringe removal algorithms,and conducts experiments on the abs DL ultracold image dataset.Experiments show that the singular value decomposition(SVD)method achieves outstanding performance,and the U-net method succeeds in implying the image inpainting idea.The main contribution of this survey is the interpretation of the fringe removal algorithms,which may help readers have a better understanding of the research status.
基金National Natural Science Foundation of China(62005248,62075193)Natural Science Foundation of Zhejiang Province(LD22F050002)Major Scientific Project of Zhejiang Laboratory(2019MB0AD01,2022MB0AL02)
文摘The nanomechanical resonator based on a levitated particle exhibits unique advantages in the development of ultrasensitive electric field detectors. We demonstrate a three-dimensional, high-sensitivity electric field measurement technology using the optically levitated nanoparticle with known net charge. By scanning the relative position between nanoparticle and parallel electrodes, the three-dimensional electric field distribution with microscale resolution is obtained. The measured noise equivalent electric intensity with charges of 100e reaches the order of 1 μV·cm^(-1)·Hz^(-1/2)at 1.4 × 10^(-7) mbar. Linearity analysis near resonance frequency shows a measured linear range over 91 d B limited only by the maximum output voltage of the driving equipment. This work may provide an avenue for developing a high-sensitivity electric field sensor based on an optically levitated nano-resonator.
基金supported by the National Natural Science Foundation of China(Grant Nos.62075193,11304282,and 61601405)Joint Fund of Ministry ofEducation,China(Grant No.6141A02011604)+2 种基金Major Scientific Research Project of Zhejiang Lab,China(Grant No.2019MB0AD01)National Program for Special Support of Top-Notch Young Professionals,China(Grant No.W02070390)Fundamental Research Funds for the Central Universities,China(Grant Nos.2016XZZX004-01 and 2018XZZX001-08).
文摘Sensing sensitivity is the key performance of optical tweezers.By adjusting the frequency and magnitude of an applied Coulomb force as an input of optical tweezers,we directly measured the sensitivity and signal-to-noise ratio(SNR)of a system and indirectly calculated the actual noise magnitude.Combined with an output filter,the relationship between the SNR and bandwidths was studied.We established the simulation model of a system using Simulink and simulated the relationship between the SNR and magnitude of the input forces and filter bandwidths.In addition,we built an experimental system to determine the relationship between the SNR and the magnitude of the input forces and filter bandwidths.The actual minimum detectable force was measured as 1.8275×10^(-17)N at a 1Hz bandwidth.The experimental results were correlated with the simulation and theoretical results,confirming the effectiveness of the proposed method and demonstrating the high sensitivity of vacuum optical tweezers as mechanical sensors.We proposed a novel method of calibration and measurement of system sensing parameters by applying an actual force that was more direct and precise than the theoretical calculation method that requires accurate fitting parameters,such as the particle radius and density.This method can be employed to analyze the system noise and phase characteristics to confirm and improve the real performance of the system.
基金Our research is supported by Major Scientific Research Project of 378 Zhejiang Lab(Grant No.2019MB0AD01)National Program for Special Support of Top-Notch Young Professionals,Fundamental Research Funds for the Central Universities 380(Grant Nos.2016XZZX004-01 and 2018 XZZX001-08)。
文摘Optical trap,a circularly polarized laser beam can levitate and control the rotation of microspheres in liquid medium with high stiffness.Trapping force performs as confinement while the trapped particle can be analog to a liquid floated gyroscope with three degree-of-ffeedom.In this work,we analyzed the feasibility of applying optically levitated rotor in the system.We presented the dynamic analysis and simulation of an ellipsoid micron particle.The precession motion and nutation motion of a rotating ellipsoid probe particle in optical tweezers were performed.We also analyzed the attitude changes of an optically levitated ellipsoid when there was variation of the external torque caused by deviation of the incident light that was provided.Furthermore,the trail path of the rotational axis vertex and the stabilization process of a particle of different ellipticities were simulated.We compared the movement tendencies of particles of different shapes and analyzed the selection criteria of ellipsoid rotor.These analytical formulae and simulation results are applicable to the analysis of the rotational motion of particles in optical tweezers,especially to the future research of the gyroscope effect.
文摘In recent years,levitated particles of optical traps in vacuum have shown the enormous potential for precision sensor development and new physics exploration.However,the accuracy of the sensor is still hampered by the uncertainty of the calibration factor relating the detected signal to the absolute displacement of the trapped particle.In this paper,we suggest and experimentally demonstrate a novel calibration method for optical tweezers based on free-falling particles in vacuum,where the gravitational acceleration is introduced as an absolute reference.Our work provides a calibration protocol with a great certainty and traceability,which is significant in improving the accuracy of precision sensing based on levitated optomechanical systems.
