Gold nanoparticles are gaining increasing attention due to their biological and medical applications.In this letter,we experimentally demonstrate the optical manipulation of 250-nm-diameter gold nanoparticles along an...Gold nanoparticles are gaining increasing attention due to their biological and medical applications.In this letter,we experimentally demonstrate the optical manipulation of 250-nm-diameter gold nanoparticles along an optical nanofiber（550 nm in diameter） injected by an 808-nm laser light.The nanoparticles situated in the evanescent optical field are trapped by optical gradient force and move along the direction of light propagation due to optical scattering force.The velocities reach as high as 132 μm/s at an optical power of 80 mW.展开更多
Optogenetics is a new and rapidly evolving gene and neuroengineering technology that allows optical control of specific populations of neurons without affecting other neurons in the brain at high temporal and spatial ...Optogenetics is a new and rapidly evolving gene and neuroengineering technology that allows optical control of specific populations of neurons without affecting other neurons in the brain at high temporal and spatial resolution.By heterologous expression of the light-sensitive membrane proteins,cell type-specific depolarization or hyperpolarization can be optically induced on a millisecond time scale.Optogenetics has the higher selectivity and specificity compared to traditional electrophysiological techniques and pharmaceutical methods.It has been a novel promising tool for medical research.Because of easy handling,high temporal and spatial precision,optogenetics has been applied to many aspects of nervous system research,such as tactual neural circuit,visual neural circuit,auditory neural circuit and olfactory neural circuit,as well as research of some neurological diseases.The review highlights the recent advances of optogenetics in medical study.展开更多
Optical field manipulation,an emerging frontier in photonics,demonstrates significant potential in biomedical microscopy,quantum state engineering,and micro-nano fabrication.To address the critical limitations of curr...Optical field manipulation,an emerging frontier in photonics,demonstrates significant potential in biomedical microscopy,quantum state engineering,and micro-nano fabrication.To address the critical limitations of current optical modulation technologies in achieving full-parameter precision control,we proposed a novel approach for dynamic azimuthal optical field modulation based on dual-spiral arrays.By designing spatially interleaved spiral structures with different initial radii while maintaining identical periodic parameters,we achieved continuous optical modulation spanning the full 0-2πrange in azimuthal field distribution.Through rigorous numerical simulations,we systematically established a quantitative correlation between the structural parameters and azimuthal optical field patterns,revealing,for the first time,a quasi-linear relationship between the radius difference and the resultant optical distribution.This theoretical framework advances our fundamental understanding of structured optical field manipulation as well as provides a new paradigm for programmable photonic device design,with distinct technical advantages in super-resolution imaging and optical tweezer systems.展开更多
Laser has become a powerful tool to manipulate micro-particles and atoms by radiation pressure or photophoretic force,but its effectiveness for large objects is less noticeable.Here,we report the direct observation of...Laser has become a powerful tool to manipulate micro-particles and atoms by radiation pressure or photophoretic force,but its effectiveness for large objects is less noticeable.Here,we report the direct observation of unusual light-induced attractive forces that allow manipulating centimeter-sized curved absorbing objects by a light beam.This force is attributed to the radiometric effect caused by the curvature of the vane and its magnitude and temporal responses are directly measured with a pendulum.Simulations suggest that the force arises from the bending of the vane,which results in a temperature difference of gas molecules between the concave and convex sides due to unbalanced gas convection.This large force(~4.4μN)is sufficient to rotate a motor with four curved vanes at speeds up to 600 r/min and even lifting a large vane.Manipulating macroscopic objects by light could have significant applications for solar radiationpowered near-space propulsion systems and for understanding the mechanisms of negative photophoretic forces.展开更多
The evolution of fractional vortex pairs in free space and nonlocal nonlinear media is studied.In free space,the off-axis fractional vortex pairs of the-same-sign topological charge(TC)will be merged to one integer vo...The evolution of fractional vortex pairs in free space and nonlocal nonlinear media is studied.In free space,the off-axis fractional vortex pairs of the-same-sign topological charge(TC)will be merged to one integer vortex at the beam center,which is drastically different from the dynamics of integer vortex pairs.In nonlocal nonlinear media,the conversion between the fractional vortex pair and the conventional integer vortex can be readily achieved by only tuning the input optical power.Therefore our approach provides a convenient way to control the number of vortices and thus the number of optical tweezers by adjusting the input optical power.These results may find potential applications in optical manipulation of particles.展开更多
Light carries energy and momentum,laying the physical foundation of optical manipulation that has facilitated advances in myriad scientific disciplines,ranging from biochemistry and robotics to quantum physics.Utilizi...Light carries energy and momentum,laying the physical foundation of optical manipulation that has facilitated advances in myriad scientific disciplines,ranging from biochemistry and robotics to quantum physics.Utilizing the momentum of light,optical tweezers have exemplified elegant light–matter interactions in which mechanical and optical momenta can be interchanged,whose effects are the most pronounced on micro and nano objects in fluid suspensions.In solid domains,the same momentum transfer becomes futile in the face of dramatically increased adhesion force.Effective implementation of optical manipulation should thereupon switch to the“energy”channel by involving auxiliary physical fields,which also coincides with the irresistible trend of enriching actuation mechanisms beyond sole reliance on light-momentum-based optical force.From this perspective,this review covers the developments of optical manipulation in schemes of both momentum and energy transfer,and we have correspondingly selected representative techniques to present.Theoretical analyses are provided at the beginning of this review followed by experimental embodiments,with special emphasis on the contrast between mechanisms and the practical realization of optical manipulation in fluid and solid domains.展开更多
Optical traps use focused laser beams to generate forces on targeted objects ranging in size from nanometers to micrometers. However, for their high coefficients of scattering and absorption, micrometer-sized metallic...Optical traps use focused laser beams to generate forces on targeted objects ranging in size from nanometers to micrometers. However, for their high coefficients of scattering and absorption, micrometer-sized metallic particles were deemed non-trappable in three dimensions using a single beam. This barrier is now removed. We demon- strate, both in theory and experiment, three-dimensional （3D） dynamic all-optical manipulations of micrometer- sized gold particles under high focusing conditions. The force of gravity is found to balance the positive axial optical force exerted on particles in an inverted optical tweezers system to form two trapping positions along the vertical direction. Both theoretical and experimental results confirm that stable 3D manipulations are achievable for these particles regardl for a variety of in-depth ess of beam polarization and wavelength. research requiting metallic particles. The present work opens up new opportunities .展开更多
Optical angular momentum(AM),comprising spin angular momentum(SAM)and orbital angular momentum(OAM),is crucial in various applications,yet its flexible control remains challenging.This study proposes,to our knowledge,...Optical angular momentum(AM),comprising spin angular momentum(SAM)and orbital angular momentum(OAM),is crucial in various applications,yet its flexible control remains challenging.This study proposes,to our knowledge,a novel method for manipulating SAM and OAM using spherical wave illumination and theΛ-shaped spiral aperture.By adjusting the spherical wave's convergence or divergence,the sign of SAM and OAM can be switched,while the geometric topological charge of the aperture transfers to the optical AM due to AM conservation.The method is theoretically analyzed,simulated,and experimentally validated,offering a compact platform applicable to photonic systems,particle manipulation,and encryption.展开更多
We report on a method to achieve multiple microscopic particles being trapped and manipulated transversely by using a size-tunable Bessel beam generated by cross-phase modulation(XPM)based on the thermal nonlinear opt...We report on a method to achieve multiple microscopic particles being trapped and manipulated transversely by using a size-tunable Bessel beam generated by cross-phase modulation(XPM)based on the thermal nonlinear optical effect.The results demonstrate that multiple polystyrene particles can be stably trapped simultaneously,and the number of the trapped particles can be controlled by varying the trapping beam power.In addition,the trapped particles can be manipulated laterally with micron-level precision by changing the size of J_(0)Bessel beam.This work provides a simple but efficient way to trap and manipulate multiple particles simultaneously,which would have potential applications in many fields such as cell sorting and transportation.展开更多
We show experimentally that when an unfocused continuous wave（CW） laser beam is obliquely incident onto the surface of a millimeter-sized mineral oil drop on sucrose solution, it will exert a pushing force on the oi...We show experimentally that when an unfocused continuous wave（CW） laser beam is obliquely incident onto the surface of a millimeter-sized mineral oil drop on sucrose solution, it will exert a pushing force on the oil drop, making it move forwards along the surface of the sucrose solution. However, after a period of time, the oil drop stops moving. This can be explained as the phenomenon caused by the change of Abraham momentum, the optical gradient force, and friction together.展开更多
An efficient on-chip platform for generating customizable vectorial optical fields is crucial and highly-pursued.While on-chip metasurfaces have opened up avenues for multi-functional coupling from on-chip surface wav...An efficient on-chip platform for generating customizable vectorial optical fields is crucial and highly-pursued.While on-chip metasurfaces have opened up avenues for multi-functional coupling from on-chip surface wave to free-space propagating wave,they typically encounter the trade-off between extraction efficiency and wavefront accuracy.Recently,Prof.Lei Zhou’s group pioneered a strategy employing geometric metal meta-atoms with low polarization conversion ratio to overcome this bottleneck and experimentally demonstrated generation of pre-designed terahertz vector beams with efficiency exceeding 90%.This approach establishes a generic,high-performance framework for advanced on-chip meta-devices.展开更多
Recently, numerous biological macromolecular experiments have been conducted with optical tweezers. For the single molecular stretching experiment with optical tweezers, three ways to determine the initial adhesion po...Recently, numerous biological macromolecular experiments have been conducted with optical tweezers. For the single molecular stretching experiment with optical tweezers, three ways to determine the initial adhesion point of DNA on the coverslip are described in this work. In addition, a new method through analyzing the displacement variance of the trapped particle to obtain the trap height is introduced. Using our proposed methods, the obtained force-extension curve for the operated dsDNA agrees well with the worm-like chain model. These improved methods are also applicable to other related biological macromolecular experiments requiring high precision.展开更多
The perfect hybrid vector vortex beam(PHVVB)with helical phase wavefront structure has aroused significant concern in recent years,as its beam waist does not expand with the topological charge(TC).In this work,we inve...The perfect hybrid vector vortex beam(PHVVB)with helical phase wavefront structure has aroused significant concern in recent years,as its beam waist does not expand with the topological charge(TC).In this work,we investigate the spatial quantum coherent modulation effect with PHVVB based on the atomic medium,and we observe the absorption characteristic of the PHVVB with different TCs under variant magnetic fields.We find that the transmission spectrum linewidth of PHVVB can be effectively maintained regardless of the TC.Still,the width of transmission peaks increases slightly as the beam size expands in hot atomic vapor.This distinctive quantum coherence phenomenon,demonstrated by the interaction of an atomic medium with a hybrid vector-structured beam,might be anticipated to open up new opportunities for quantum coherence modulation and accurate magnetic field measurement.展开更多
A recent study demonstrated advancements in quantum computing by applying it to address a non-Hermitian optical manipulation problem.The emergence of exceptional points and the dynamics of optically trapped single or ...A recent study demonstrated advancements in quantum computing by applying it to address a non-Hermitian optical manipulation problem.The emergence of exceptional points and the dynamics of optically trapped single or multiple particles were simulated using a quantum computing approach.展开更多
Over the past few decades,metasurfaces have revolutionized conventional bulky optics by providing an effective approach to manipulate optical waves at the subwavelength scale.This advancement holds great potential for...Over the past few decades,metasurfaces have revolutionized conventional bulky optics by providing an effective approach to manipulate optical waves at the subwavelength scale.This advancement holds great potential for compact,multifunctional,and reconfigurable optical devices.Notably,metasurfaces constructed with anisotropic nanostructures have exhibited remarkable capability in manipulating the polarization state of optical waves.Furthermore,they can be employed to achieve independent control of the amplitude and phase of optical waves in different polarization channels.This capability has garnered significant attention from the photonics community due to its unprecedented potential for polarization-selective and-multiplexed optical wave manipulation,offering versatile applications in optical imaging,communication,and detection.This paper reviews the design principles,representative works,and recent advancements in anisotropic nanostructures for optical polarization manipulation,detection,as well as polarization-selective and-multiplexed optical wave manipulation.Personal insights into further developments in this research area are provided.展开更多
In recent years,optical skyrmions have garnered increasing attention for their ability to introduce new degrees of freedom in manipulating optical fields.While most research has focused on creating innovative optical ...In recent years,optical skyrmions have garnered increasing attention for their ability to introduce new degrees of freedom in manipulating optical fields.While most research has focused on creating innovative optical topological states such as merons and hopfions,there has been limited exploration into their manipulation,which hinders practical applications in this field.In this study,we utilize a hybrid multi-zone filter to induce a Hall effect-like splitting of optical Stokes skyrmions(HESSs),enabling effective separation and manipulation.By manipulating the horizontal phase gradient parameter,we independently control the separation angle of skyrmions.Additionally,we demonstrate control over the topological charge parameter to achieve symmetric and asymmetric HESSs.This effect not only enhances the manipulation capabilities of optical fields but also opens up potential applications for high precision displacement measurements and preservation quantum information.展开更多
An optical trap forms a restoring optical force field to immobilize and manipulate tiny objects.A fiber optical trap is capable of establishing the restoring optical force field using one or a few pieces of optical fi...An optical trap forms a restoring optical force field to immobilize and manipulate tiny objects.A fiber optical trap is capable of establishing the restoring optical force field using one or a few pieces of optical fiber,and it greatly simplifies the optical setup by removing bulky optical components,such as microscope objectives from the working space.It also inherits other major advantages of optical fibers:flexible in shape,robust against disturbance,and highly integrative with fiber-optic sys-tems and on-chip devices.This review will begin with a concise introduction on the principle of optical trapping techniques,followed by a comprehensive discussion on different types of fiber optical traps,including their structures,functionalities and associated fabrication techniques.A brief outlook to the future development and potential applications of fiber optical traps is given at the end.展开更多
A phase-only method is proposed to transform an optical vortex field into desired spiral diffraction-interference patterns.Double-ring phase apertures are designed to produce a concentric high-order vortex beam and a ...A phase-only method is proposed to transform an optical vortex field into desired spiral diffraction-interference patterns.Double-ring phase apertures are designed to produce a concentric high-order vortex beam and a zeroth-order vortex beam,and the diffracted intensity ratio of two beams is adjustable between 0 and 1.The coherent superposition of the two diffracted beams generates a brighter Airy spot(or Poisson spot)in the middle of the spiral pattern,where the singularity for typical vortex beam is located.Experiments employing circular,triangular,and rectangular phase apertures with topological charges from 3 to 16 demonstrate a stable,compact,and flexible apparatus for vortex beam conversion.By adjusting the parameters of the phase aperture,the proposed method can realize the optical Gaussian tweezer function and the optical vortex tweezer function simultaneously along the same axis or switch the experimental setup between the two functions.It also has potential applications in light communication through turbulent air by transmitting an orbital angular momentum-coded signal with a concentric beacon laser.展开更多
Light carries linear momentum and can therefore exert a radiation force on the objects that it encounters. This established fact enabled optical manipulation of micro/nano-sized objects, as well as macroscopic objects...Light carries linear momentum and can therefore exert a radiation force on the objects that it encounters. This established fact enabled optical manipulation of micro/nano-sized objects, as well as macroscopic objects such as solar sails, among many other important applications. While these efforts benefit from the average value of light’s linear momentum, in this article, we propose exploiting the temporal variation of light’s linear momentum to achieve an oscillatory force of microNewton amplitude and picosecond period. We validate our proposal by analytical calculations and time domain simulations of Maxwell’s equations in the case of a high-index quarter-wave slab irradiated by a terahertz plane electromagnetic wave. In particular, we show that for plane wave terahertz light of electric field amplitude 5000 V/m and frequency 4.8 THz, an oscillatory radiation pressure of amplitude 1.8 × 10<sup>-4</sup> N/m<sup>2</sup> and 0.1 ps period can be achieved.展开更多
Optical methods to manipulate and detect nanoscale objects are highly desired in both nanomaterials and molecular biology fields.Optical tweezers have been used to manipulate objects that range in size from a few hund...Optical methods to manipulate and detect nanoscale objects are highly desired in both nanomaterials and molecular biology fields.Optical tweezers have been used to manipulate objects that range in size from a few hundred nanometres to several micrometres.The emergence of near-field methods that overcome the diffraction limit has enabled the manipulation of objects below 100 nm.A highly free manipulation with signal-enhanced real-time detection,however,remains a challenge for single sub-100-nm nanoparticles or biomolecules.Here we show an approach that uses a photonic nanojet to perform the manipulation and detection of single sub-100-nm objects.With the photonic nanojet generated by a dielectric microlens bound to an optical fibre probe,three-dimensional manipulations were achieved for a single 85-nm fluorescent polystyrene nanoparticle as well as for a plasmid DNA molecule.Backscattering and fluorescent signals were detected with the enhancement factors up to~103 and~30,respectively.The demonstrated approach provides a potentially powerful tool for nanostructure assembly,biosensing and single-biomolecule studies.展开更多
文摘Gold nanoparticles are gaining increasing attention due to their biological and medical applications.In this letter,we experimentally demonstrate the optical manipulation of 250-nm-diameter gold nanoparticles along an optical nanofiber（550 nm in diameter） injected by an 808-nm laser light.The nanoparticles situated in the evanescent optical field are trapped by optical gradient force and move along the direction of light propagation due to optical scattering force.The velocities reach as high as 132 μm/s at an optical power of 80 mW.
基金National Natural Sciences Foundation of China(No.81070749)Chongqing Science and Technology Project,China(No.CSTC,2010AB5118)
文摘Optogenetics is a new and rapidly evolving gene and neuroengineering technology that allows optical control of specific populations of neurons without affecting other neurons in the brain at high temporal and spatial resolution.By heterologous expression of the light-sensitive membrane proteins,cell type-specific depolarization or hyperpolarization can be optically induced on a millisecond time scale.Optogenetics has the higher selectivity and specificity compared to traditional electrophysiological techniques and pharmaceutical methods.It has been a novel promising tool for medical research.Because of easy handling,high temporal and spatial precision,optogenetics has been applied to many aspects of nervous system research,such as tactual neural circuit,visual neural circuit,auditory neural circuit and olfactory neural circuit,as well as research of some neurological diseases.The review highlights the recent advances of optogenetics in medical study.
文摘Optical field manipulation,an emerging frontier in photonics,demonstrates significant potential in biomedical microscopy,quantum state engineering,and micro-nano fabrication.To address the critical limitations of current optical modulation technologies in achieving full-parameter precision control,we proposed a novel approach for dynamic azimuthal optical field modulation based on dual-spiral arrays.By designing spatially interleaved spiral structures with different initial radii while maintaining identical periodic parameters,we achieved continuous optical modulation spanning the full 0-2πrange in azimuthal field distribution.Through rigorous numerical simulations,we systematically established a quantitative correlation between the structural parameters and azimuthal optical field patterns,revealing,for the first time,a quasi-linear relationship between the radius difference and the resultant optical distribution.This theoretical framework advances our fundamental understanding of structured optical field manipulation as well as provides a new paradigm for programmable photonic device design,with distinct technical advantages in super-resolution imaging and optical tweezer systems.
基金supported by the National Natural Science Foundation of China(Grant No.61775036)the high-level talents program of Dongguan University of Technology(Grant No.KCYCXPT2017003).
文摘Laser has become a powerful tool to manipulate micro-particles and atoms by radiation pressure or photophoretic force,but its effectiveness for large objects is less noticeable.Here,we report the direct observation of unusual light-induced attractive forces that allow manipulating centimeter-sized curved absorbing objects by a light beam.This force is attributed to the radiometric effect caused by the curvature of the vane and its magnitude and temporal responses are directly measured with a pendulum.Simulations suggest that the force arises from the bending of the vane,which results in a temperature difference of gas molecules between the concave and convex sides due to unbalanced gas convection.This large force(~4.4μN)is sufficient to rotate a motor with four curved vanes at speeds up to 600 r/min and even lifting a large vane.Manipulating macroscopic objects by light could have significant applications for solar radiationpowered near-space propulsion systems and for understanding the mechanisms of negative photophoretic forces.
基金supported by the International Scientific and Technological Cooperation Projects of Henan Province,China(Grant No.242102520010)the Natural Science Foundation of Henan Province,China(Grant No.252300421307)the Training Program for Young Backbone Teachers of Higher Education Institutions in Henan Province,China(Grant No.2023GGJS130).
文摘The evolution of fractional vortex pairs in free space and nonlocal nonlinear media is studied.In free space,the off-axis fractional vortex pairs of the-same-sign topological charge(TC)will be merged to one integer vortex at the beam center,which is drastically different from the dynamics of integer vortex pairs.In nonlocal nonlinear media,the conversion between the fractional vortex pair and the conventional integer vortex can be readily achieved by only tuning the input optical power.Therefore our approach provides a convenient way to control the number of vortices and thus the number of optical tweezers by adjusting the input optical power.These results may find potential applications in optical manipulation of particles.
基金supported by the National Natural Science Foundation of China (Nos.61927820,61905201,and 62275221).
文摘Light carries energy and momentum,laying the physical foundation of optical manipulation that has facilitated advances in myriad scientific disciplines,ranging from biochemistry and robotics to quantum physics.Utilizing the momentum of light,optical tweezers have exemplified elegant light–matter interactions in which mechanical and optical momenta can be interchanged,whose effects are the most pronounced on micro and nano objects in fluid suspensions.In solid domains,the same momentum transfer becomes futile in the face of dramatically increased adhesion force.Effective implementation of optical manipulation should thereupon switch to the“energy”channel by involving auxiliary physical fields,which also coincides with the irresistible trend of enriching actuation mechanisms beyond sole reliance on light-momentum-based optical force.From this perspective,this review covers the developments of optical manipulation in schemes of both momentum and energy transfer,and we have correspondingly selected representative techniques to present.Theoretical analyses are provided at the beginning of this review followed by experimental embodiments,with special emphasis on the contrast between mechanisms and the practical realization of optical manipulation in fluid and solid domains.
基金National Natural Science Foundation of China(NSFC)(91750205,61377052,61422506,61427819,61605117)National Key Basic Research Program of China(973)(2015CB352004)+3 种基金National Key Research and Development Program of China(2016YFC0102401)Leading Talents of Guangdong Province Program(00201505)Natural Science Foundation of Guangdong Province(2016A030312010,2016A030310063)Excellent Young Teacher Program of Guangdong Province(YQ2014151)
文摘Optical traps use focused laser beams to generate forces on targeted objects ranging in size from nanometers to micrometers. However, for their high coefficients of scattering and absorption, micrometer-sized metallic particles were deemed non-trappable in three dimensions using a single beam. This barrier is now removed. We demon- strate, both in theory and experiment, three-dimensional （3D） dynamic all-optical manipulations of micrometer- sized gold particles under high focusing conditions. The force of gravity is found to balance the positive axial optical force exerted on particles in an inverted optical tweezers system to form two trapping positions along the vertical direction. Both theoretical and experimental results confirm that stable 3D manipulations are achievable for these particles regardl for a variety of in-depth ess of beam polarization and wavelength. research requiting metallic particles. The present work opens up new opportunities .
基金supported by the National Key Research and Development Program of China(Nos.2023YFF0715501and 2023YFF0715502)the Anhui Provincial Science and Technology Breakthrough Plan Project(No.202423k09020046)+1 种基金the Anhui Provincial Key Research and Development Project(No.202304a05020009)the Technology Domain Fund of 173 Project(No.2021-Jc JQ-JJ-0284)。
文摘Optical angular momentum(AM),comprising spin angular momentum(SAM)and orbital angular momentum(OAM),is crucial in various applications,yet its flexible control remains challenging.This study proposes,to our knowledge,a novel method for manipulating SAM and OAM using spherical wave illumination and theΛ-shaped spiral aperture.By adjusting the spherical wave's convergence or divergence,the sign of SAM and OAM can be switched,while the geometric topological charge of the aperture transfers to the optical AM due to AM conservation.The method is theoretically analyzed,simulated,and experimentally validated,offering a compact platform applicable to photonic systems,particle manipulation,and encryption.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61805200,51927804,and12104365)the Natural Science Foundation of Shaanxi Province,China(Grant No.2020JM-432)+1 种基金the Fund for Young Star in Science and Technology of Shaanxi Province,China(Grant No.2021KJXX-27)the Fund from the Education Department of Shaanxi Province,China(Grant No.21JK0915)。
文摘We report on a method to achieve multiple microscopic particles being trapped and manipulated transversely by using a size-tunable Bessel beam generated by cross-phase modulation(XPM)based on the thermal nonlinear optical effect.The results demonstrate that multiple polystyrene particles can be stably trapped simultaneously,and the number of the trapped particles can be controlled by varying the trapping beam power.In addition,the trapped particles can be manipulated laterally with micron-level precision by changing the size of J_(0)Bessel beam.This work provides a simple but efficient way to trap and manipulate multiple particles simultaneously,which would have potential applications in many fields such as cell sorting and transportation.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.90921009 and 11274401)
文摘We show experimentally that when an unfocused continuous wave（CW） laser beam is obliquely incident onto the surface of a millimeter-sized mineral oil drop on sucrose solution, it will exert a pushing force on the oil drop, making it move forwards along the surface of the sucrose solution. However, after a period of time, the oil drop stops moving. This can be explained as the phenomenon caused by the change of Abraham momentum, the optical gradient force, and friction together.
基金support by the National Natural Science Foundation of China(Grant Nos.62325504,92250304,and 12174186)Dengfeng Project B of Nanjing University.
文摘An efficient on-chip platform for generating customizable vectorial optical fields is crucial and highly-pursued.While on-chip metasurfaces have opened up avenues for multi-functional coupling from on-chip surface wave to free-space propagating wave,they typically encounter the trade-off between extraction efficiency and wavefront accuracy.Recently,Prof.Lei Zhou’s group pioneered a strategy employing geometric metal meta-atoms with low polarization conversion ratio to overcome this bottleneck and experimentally demonstrated generation of pre-designed terahertz vector beams with efficiency exceeding 90%.This approach establishes a generic,high-performance framework for advanced on-chip meta-devices.
基金Supported by the National Natural Science Foundation of China under Grant No 91023049the National Basic Research Program of China under Grant No 2012CB937500
文摘Recently, numerous biological macromolecular experiments have been conducted with optical tweezers. For the single molecular stretching experiment with optical tweezers, three ways to determine the initial adhesion point of DNA on the coverslip are described in this work. In addition, a new method through analyzing the displacement variance of the trapped particle to obtain the trap height is introduced. Using our proposed methods, the obtained force-extension curve for the operated dsDNA agrees well with the worm-like chain model. These improved methods are also applicable to other related biological macromolecular experiments requiring high precision.
基金Project supported by the Youth Innovation Promotion Association CASState Key Laboratory of Transient Optics and Photonics Open Topics (Grant No. SKLST202222)
文摘The perfect hybrid vector vortex beam(PHVVB)with helical phase wavefront structure has aroused significant concern in recent years,as its beam waist does not expand with the topological charge(TC).In this work,we investigate the spatial quantum coherent modulation effect with PHVVB based on the atomic medium,and we observe the absorption characteristic of the PHVVB with different TCs under variant magnetic fields.We find that the transmission spectrum linewidth of PHVVB can be effectively maintained regardless of the TC.Still,the width of transmission peaks increases slightly as the beam size expands in hot atomic vapor.This distinctive quantum coherence phenomenon,demonstrated by the interaction of an atomic medium with a hybrid vector-structured beam,might be anticipated to open up new opportunities for quantum coherence modulation and accurate magnetic field measurement.
文摘A recent study demonstrated advancements in quantum computing by applying it to address a non-Hermitian optical manipulation problem.The emergence of exceptional points and the dynamics of optically trapped single or multiple particles were simulated using a quantum computing approach.
基金supported by the National Key Research and Development Program of China(Nos.2021YFA1400601 and 2022YFA1404501)the National Natural Science Fund for Distinguished Young Scholars(No.11925403)the New Cornerstone Science Foundation,the National Natural Science Foundation of China(Nos.12122406,12192253,U22A20258,12274237 and 12274239)。
文摘Over the past few decades,metasurfaces have revolutionized conventional bulky optics by providing an effective approach to manipulate optical waves at the subwavelength scale.This advancement holds great potential for compact,multifunctional,and reconfigurable optical devices.Notably,metasurfaces constructed with anisotropic nanostructures have exhibited remarkable capability in manipulating the polarization state of optical waves.Furthermore,they can be employed to achieve independent control of the amplitude and phase of optical waves in different polarization channels.This capability has garnered significant attention from the photonics community due to its unprecedented potential for polarization-selective and-multiplexed optical wave manipulation,offering versatile applications in optical imaging,communication,and detection.This paper reviews the design principles,representative works,and recent advancements in anisotropic nanostructures for optical polarization manipulation,detection,as well as polarization-selective and-multiplexed optical wave manipulation.Personal insights into further developments in this research area are provided.
基金Guangdong Major Project of Basic Research(2020B0301030009)National Natural Science Foundation of China(61935013,62375181,61975133)+3 种基金Shenzhen Peacock Plan(KQTD20170330110444030)Science,Technology and Innovation Commission of Shenzhen Municipality(JCYJ20200109114018750)Scientific Instrument Developing Project of Shenzhen University(2023YQ001)Shenzhen University 2035 Initiative(2023B004)。
文摘In recent years,optical skyrmions have garnered increasing attention for their ability to introduce new degrees of freedom in manipulating optical fields.While most research has focused on creating innovative optical topological states such as merons and hopfions,there has been limited exploration into their manipulation,which hinders practical applications in this field.In this study,we utilize a hybrid multi-zone filter to induce a Hall effect-like splitting of optical Stokes skyrmions(HESSs),enabling effective separation and manipulation.By manipulating the horizontal phase gradient parameter,we independently control the separation angle of skyrmions.Additionally,we demonstrate control over the topological charge parameter to achieve symmetric and asymmetric HESSs.This effect not only enhances the manipulation capabilities of optical fields but also opens up potential applications for high precision displacement measurements and preservation quantum information.
基金from National Natural Science Foundation of China(Grant number:11874164)the Innovation Fund of Wuhan National Laboratory for Optoelectronics and 1000 Talent Youth Program.
文摘An optical trap forms a restoring optical force field to immobilize and manipulate tiny objects.A fiber optical trap is capable of establishing the restoring optical force field using one or a few pieces of optical fiber,and it greatly simplifies the optical setup by removing bulky optical components,such as microscope objectives from the working space.It also inherits other major advantages of optical fibers:flexible in shape,robust against disturbance,and highly integrative with fiber-optic sys-tems and on-chip devices.This review will begin with a concise introduction on the principle of optical trapping techniques,followed by a comprehensive discussion on different types of fiber optical traps,including their structures,functionalities and associated fabrication techniques.A brief outlook to the future development and potential applications of fiber optical traps is given at the end.
基金supported by the National Natural Science Foundation of China(Grant Nos.T2293753 and T2293750)the Major Science and Technology Project in Hainan Province of China(Grant No.ZDKJ2019012).
文摘A phase-only method is proposed to transform an optical vortex field into desired spiral diffraction-interference patterns.Double-ring phase apertures are designed to produce a concentric high-order vortex beam and a zeroth-order vortex beam,and the diffracted intensity ratio of two beams is adjustable between 0 and 1.The coherent superposition of the two diffracted beams generates a brighter Airy spot(or Poisson spot)in the middle of the spiral pattern,where the singularity for typical vortex beam is located.Experiments employing circular,triangular,and rectangular phase apertures with topological charges from 3 to 16 demonstrate a stable,compact,and flexible apparatus for vortex beam conversion.By adjusting the parameters of the phase aperture,the proposed method can realize the optical Gaussian tweezer function and the optical vortex tweezer function simultaneously along the same axis or switch the experimental setup between the two functions.It also has potential applications in light communication through turbulent air by transmitting an orbital angular momentum-coded signal with a concentric beacon laser.
文摘Light carries linear momentum and can therefore exert a radiation force on the objects that it encounters. This established fact enabled optical manipulation of micro/nano-sized objects, as well as macroscopic objects such as solar sails, among many other important applications. While these efforts benefit from the average value of light’s linear momentum, in this article, we propose exploiting the temporal variation of light’s linear momentum to achieve an oscillatory force of microNewton amplitude and picosecond period. We validate our proposal by analytical calculations and time domain simulations of Maxwell’s equations in the case of a high-index quarter-wave slab irradiated by a terahertz plane electromagnetic wave. In particular, we show that for plane wave terahertz light of electric field amplitude 5000 V/m and frequency 4.8 THz, an oscillatory radiation pressure of amplitude 1.8 × 10<sup>-4</sup> N/m<sup>2</sup> and 0.1 ps period can be achieved.
基金supported by the Program for Changjiang Scholars and Innovative Research Team in University(IRT13042)the National Natural Science Foundation of China(No.61205165).
文摘Optical methods to manipulate and detect nanoscale objects are highly desired in both nanomaterials and molecular biology fields.Optical tweezers have been used to manipulate objects that range in size from a few hundred nanometres to several micrometres.The emergence of near-field methods that overcome the diffraction limit has enabled the manipulation of objects below 100 nm.A highly free manipulation with signal-enhanced real-time detection,however,remains a challenge for single sub-100-nm nanoparticles or biomolecules.Here we show an approach that uses a photonic nanojet to perform the manipulation and detection of single sub-100-nm objects.With the photonic nanojet generated by a dielectric microlens bound to an optical fibre probe,three-dimensional manipulations were achieved for a single 85-nm fluorescent polystyrene nanoparticle as well as for a plasmid DNA molecule.Backscattering and fluorescent signals were detected with the enhancement factors up to~103 and~30,respectively.The demonstrated approach provides a potentially powerful tool for nanostructure assembly,biosensing and single-biomolecule studies.
