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
We propose a simple and efficient method that uses a single focused hybrid vector beam to confine metallic Rayleigh particles at multiple positions.We study the force mechanisms of multiple trapping by analyzing the g...We propose a simple and efficient method that uses a single focused hybrid vector beam to confine metallic Rayleigh particles at multiple positions.We study the force mechanisms of multiple trapping by analyzing the gradient and scattering forces.It is observed that the wavelength and topological charges of the hybrid vector beam regulate the trapping positions and number of optical trap sites.The proposed method can be implemented easily in three-dimensional space, and it facilitates both trapping and organization of particles.Thus, it can provide an effective and controllable means for nanoparticle manipulation.展开更多
Optical trapping techniques are of great interest since they have the advantage of enabling the direct handling of nanoparticles. Among various optical trapping systems, photonic crystal nanobeam cavities have attract...Optical trapping techniques are of great interest since they have the advantage of enabling the direct handling of nanoparticles. Among various optical trapping systems, photonic crystal nanobeam cavities have attracted great attention for integrated on-chip trapping and manipulation. However, optical trapping with high efficiency and low input power is still a big challenge in nanobeam cavities because most of the light energy is confined within the solid dielectric region. To this end, by incorporating a nanoslotted structure into an ultracompact one- dimensional photonic crystal nanobeam cavity structure, we design a promising on-chip device with ultralarge trapping potential depth to enhance the optical trapping characteristic of the cavity. In this work, we first provide a systematic analysis of the optical trapping force for an airborne polystyrene （PS） nanoparticle trapped in a cavity model. Then, to validate the theoretical analysis, the numerical simulation proof is demonstrated in detail by using the three-dimensional finite element method. For trapping a PS nanoparticle of 10 nm radius within the air-slot, a maximum trapping force as high as 8.28 nN/mW and a depth of trapping potential as large as 1.15 × 105 kBTmW-1 are obtained, where kB is the Boltzmann constant and T is the system temperature. We estimate a lateral trapping stiffness of 167.17 pN. nm-1 . mW-1 for a 10 nm radius PS nanoparticle along the cavity x-axis, more than two orders of magnitude higher than previously demonstrated on-chip, near field traps. Moreover, the threshold power for stable trapping as low as 0.087 μW is achieved. In addition, trapping of a single 25 nm radius PS nanoparticle causes a 0.6 nm redshift in peak wavelength. Thus, the proposed cavity device can be used to detect single nanoparticle trapping by monitoring the resonant peak wavelength shift. We believe that the architecture with features of an ultracompact footprint, high integrahility with optical waveguides/cir- cuits, and efficient trapping demonstrat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
The laser trapping of untransmissive particles are discussed in this paper. Photon can generate the momentum tothe untransmissive particle by diffraction and reflection on the surface of the particles. We tried laser ...The laser trapping of untransmissive particles are discussed in this paper. Photon can generate the momentum tothe untransmissive particle by diffraction and reflection on the surface of the particles. We tried laser trapping ofuntransmissive particles using an attractive force caused by the diffraction and radiation force caused by reflection.The laser trapping system includes CW YAG laser, which has 1.064 μm in wave length and an optical microscope.The motions of particles were monitored by a CCD camera on the top of the microscope and recordedby PC connected to the CCD camera.展开更多
a team led by Prof.Zheng Hairong of Shenzhen Institutes of Advanced Technology has obtained continuous achievements on acoustic manipulation of micro-particles,a single cell’s reparable sonoporation,and reversal of m...a team led by Prof.Zheng Hairong of Shenzhen Institutes of Advanced Technology has obtained continuous achievements on acoustic manipulation of micro-particles,a single cell’s reparable sonoporation,and reversal of multidrug resistance phenotype in cancer cells via ultrasound targeted microbubble destruction(UTMD)technology,which were published in Physical Review Applied(2014,1:051001),Applied Physics Letters(2014,104:073701),and Journal of Con-展开更多
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Project supported by the National Natural Science Foundation of China(Grant Nos.11604050,91636109,61575041,and 61875242)the Fundamental Research Funds for the Central Universities at Xiamen University,China(Grant No.20720190057)+3 种基金the Natural Science Foundation of Fujian Province of China for Distinguished Young Scientists(Grant No.2015J06002)the Program for New Century Excellent Talents in University of China(Grant No.NCET-13-0495)the Science and Technology Planning Project of Guangdong Province,China(Grant No.2016B010113004)the Natural Science Foundation of Guangdong Province,China(Grant Nos.2015A030310296 and 2018A030313347)
文摘We propose a simple and efficient method that uses a single focused hybrid vector beam to confine metallic Rayleigh particles at multiple positions.We study the force mechanisms of multiple trapping by analyzing the gradient and scattering forces.It is observed that the wavelength and topological charges of the hybrid vector beam regulate the trapping positions and number of optical trap sites.The proposed method can be implemented easily in three-dimensional space, and it facilitates both trapping and organization of particles.Thus, it can provide an effective and controllable means for nanoparticle manipulation.
基金National Natural Science Foundation of China(NSFC)(61501053,61611540346,11474011,11654003,61435001,61471050,61622103)National Key R&D Program of China(2016YFA0301302)+1 种基金Fund of the State Key Laboratory of Information Photonics and Optical Communications(IPOC2017ZT05)Beijing University of Posts and Telecommunications,China
文摘Optical trapping techniques are of great interest since they have the advantage of enabling the direct handling of nanoparticles. Among various optical trapping systems, photonic crystal nanobeam cavities have attracted great attention for integrated on-chip trapping and manipulation. However, optical trapping with high efficiency and low input power is still a big challenge in nanobeam cavities because most of the light energy is confined within the solid dielectric region. To this end, by incorporating a nanoslotted structure into an ultracompact one- dimensional photonic crystal nanobeam cavity structure, we design a promising on-chip device with ultralarge trapping potential depth to enhance the optical trapping characteristic of the cavity. In this work, we first provide a systematic analysis of the optical trapping force for an airborne polystyrene （PS） nanoparticle trapped in a cavity model. Then, to validate the theoretical analysis, the numerical simulation proof is demonstrated in detail by using the three-dimensional finite element method. For trapping a PS nanoparticle of 10 nm radius within the air-slot, a maximum trapping force as high as 8.28 nN/mW and a depth of trapping potential as large as 1.15 × 105 kBTmW-1 are obtained, where kB is the Boltzmann constant and T is the system temperature. We estimate a lateral trapping stiffness of 167.17 pN. nm-1 . mW-1 for a 10 nm radius PS nanoparticle along the cavity x-axis, more than two orders of magnitude higher than previously demonstrated on-chip, near field traps. Moreover, the threshold power for stable trapping as low as 0.087 μW is achieved. In addition, trapping of a single 25 nm radius PS nanoparticle causes a 0.6 nm redshift in peak wavelength. Thus, the proposed cavity device can be used to detect single nanoparticle trapping by monitoring the resonant peak wavelength shift. We believe that the architecture with features of an ultracompact footprint, high integrahility with optical waveguides/cir- cuits, and efficient trapping demonstrat
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.
文摘The laser trapping of untransmissive particles are discussed in this paper. Photon can generate the momentum tothe untransmissive particle by diffraction and reflection on the surface of the particles. We tried laser trapping ofuntransmissive particles using an attractive force caused by the diffraction and radiation force caused by reflection.The laser trapping system includes CW YAG laser, which has 1.064 μm in wave length and an optical microscope.The motions of particles were monitored by a CCD camera on the top of the microscope and recordedby PC connected to the CCD camera.
基金support by the National Natural Science Foundation of China(Grant Nos.11325420,11274008,11304341 and 81371563)
文摘a team led by Prof.Zheng Hairong of Shenzhen Institutes of Advanced Technology has obtained continuous achievements on acoustic manipulation of micro-particles,a single cell’s reparable sonoporation,and reversal of multidrug resistance phenotype in cancer cells via ultrasound targeted microbubble destruction(UTMD)technology,which were published in Physical Review Applied(2014,1:051001),Applied Physics Letters(2014,104:073701),and Journal of Con-
