The rotation control of particles in optical tweezers is often subject to the spin or orbit angular momentum induced optical torque,which is susceptible to the mechanical and morphological properties of individual par...The rotation control of particles in optical tweezers is often subject to the spin or orbit angular momentum induced optical torque,which is susceptible to the mechanical and morphological properties of individual particle.Here we report on a robust and high-speed rotation control in optical tweezers by using a novel linear polarization synthesis based on optical heterodyne interference between two circularly polarized lights with opposite handedness.The synthesized linear polarization can be rotated in a hopping-free scheme at arbitrary speed determined electronically by the heterodyne frequency between two laser fields.The experimental demonstration of a trapped vaterite particle in water shows that the precisely controlled rotation frequency of 300 Hz can be achieved.The proposed method will find promising applications in optically driven micro-gears,fluidic pumps and rotational micro-rheology.展开更多
Precise information about the temporal mode of optical states is crucial for optimizing their interaction efficiency between themselves and/or with matter in various quantum communication devices.Here we propose and e...Precise information about the temporal mode of optical states is crucial for optimizing their interaction efficiency between themselves and/or with matter in various quantum communication devices.Here we propose and experimentally demonstrate a method of determining both the real and imaginary components of a single photon’s temporal density matrix by measuring the autocorrelation function of the photocurrent from a balanced homodyne detector at multiple local oscillator frequencies.We test our method on single photons heralded from biphotons generated via four-wave mixing in an atomic vapor and obtain excellent agreement with theoretical predictions for several settings.展开更多
基金the National Natural Science Foundation of China(91750203 and 91850111)State Key Laboratory of Applied Optics,Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences and the High-performance Computing Platform of Peking University.
文摘The rotation control of particles in optical tweezers is often subject to the spin or orbit angular momentum induced optical torque,which is susceptible to the mechanical and morphological properties of individual particle.Here we report on a robust and high-speed rotation control in optical tweezers by using a novel linear polarization synthesis based on optical heterodyne interference between two circularly polarized lights with opposite handedness.The synthesized linear polarization can be rotated in a hopping-free scheme at arbitrary speed determined electronically by the heterodyne frequency between two laser fields.The experimental demonstration of a trapped vaterite particle in water shows that the precisely controlled rotation frequency of 300 Hz can be achieved.The proposed method will find promising applications in optically driven micro-gears,fluidic pumps and rotational micro-rheology.
基金The project is supported by NSERC and CIFAR.AL is a CIFAR FellowZQ is supported by the China Scholarship Council
文摘Precise information about the temporal mode of optical states is crucial for optimizing their interaction efficiency between themselves and/or with matter in various quantum communication devices.Here we propose and experimentally demonstrate a method of determining both the real and imaginary components of a single photon’s temporal density matrix by measuring the autocorrelation function of the photocurrent from a balanced homodyne detector at multiple local oscillator frequencies.We test our method on single photons heralded from biphotons generated via four-wave mixing in an atomic vapor and obtain excellent agreement with theoretical predictions for several settings.
