Generation and Propagation of Partially Coherent Power-Exponent-Phase Vortex Beam

We report on a partially coherent power-exponent-phase vortex beam (PC-PEPV), whose spatial coherence is controllable and the initial phase exhibits a periodic power exponential change. The PC-PEPV beam was generated experimentally with various spatial coherence widths, and its propagation properties were studied both numerically and experimentally. By modulating the topological charge (TC) and power order of the PC-PEPV beam, the structure of the vortex beam can be adjusted from circular to elliptic, triangular, quadrangle, and pentagon. When the power order is odd, the PC-PEPV beam with a negative TC can be generated, and the profiles of the PC-PEPV beam can be precisely controlled via adjusting the value of the power order. For the case of high spatial coherence width, the number of the dark cores in the polygonal intensity array of the PC-PEPV beam equals the magnitude of the TC. However, when decreasing the spatial coherence width, the dark cores vanish and the intensity gradually transforms into a polygonal light spot. Fortunately, from the modulus and phase distributions of the cross-spectral density (CSD), both the magnitude and sign of the TC can be determined. In the experiment, the modulus and phase distribution of the CSD are verified by the phase perturbation method. This study has potential applications in beam shaping, micro-particle trapping, and optical tweezers.

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The Propagation Characteristics of Partially Coherent Power-Exponent-Phase-Vortex Beam*

Acta Physica Sinica ◽

10.7498/aps.70.20211411 ◽

2021 ◽

Vol 0 (0) ◽

pp. 0-0

Author(s):

Keyword(s):

Power Exponent ◽

Vortex Beam ◽

Propagation Characteristics ◽

Partially Coherent

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Spatial Coherence Manipulation on the Statistical Photonic Platform

10.21203/rs.3.rs-888780/v1 ◽

2021 ◽

Author(s):

Leixin Liu ◽

Wenwei Liu ◽

Fei Wang ◽

Hua Cheng ◽

Duk-Yong Choi ◽

...

Keyword(s):

Phase Distribution ◽

Random Phase ◽

Spatial Coherence ◽

Light Fields ◽

Optical Components ◽

Partially Coherent ◽

Optical Media ◽

Partially Coherent Light ◽

Coherent Beams ◽

Coherent Vortex

Abstract Coherence, like amplitude, polarization and phase, is a fundamental characteristic of the light fields and is dominated by the statistical optical property. Generally, accurate coherence manipulation is challenging since coherence as a statistical quantity requires the combination of various bulky optical components and fast tuning of optical media. Spatial coherence as another pivotal optical dimension still has not been significantly manipulated on the photonic platform. Here, we theoretically and experimentally realize accurate manipulation of the spatial coherence of light fields by loading a temporal random phase distribution onto the wave-front on the statistical photonic platform. By quantitatively manipulating the statistical photonic properties, we can successfully achieve the partially coherent light with the pre-defined degree of coherence and continuously modulate it from fully coherent to incoherent. This design strategy can also be easily extended to manipulate the spatial coherence of other special beams such as partially coherent vortex beam generations. Our approach provides straightforward rules to manipulate the coherence of the light fields and paves the way for applications of partially coherent beams in information encryption, ghost imaging, and information transmission in turbulent media.

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Optical vortex lattice: an exploitation of orbital angular momentum

Nanophotonics ◽

10.1515/nanoph-2021-0139 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Liuhao Zhu ◽

Miaomiao Tang ◽

Hehe Li ◽

Yuping Tai ◽

Xinzhong Li

Keyword(s):

Angular Momentum ◽

Optical Tweezers ◽

Orbital Angular Momentum ◽

Vortex Lattice ◽

Optical Vortex ◽

Yeast Cells ◽

Particle Manipulation ◽

Complex Motion ◽

Potential Applications ◽

Vortex Beams

Abstract Generally, an optical vortex lattice (OVL) is generated via the superposition of two specific vortex beams. Thus far, OVL has been successfully employed to trap atoms via the dark cores. The topological charge (TC) on each optical vortex (OV) in the lattice is only ±1. Consequently, the orbital angular momentum (OAM) on the lattice is ignored. To expand the potential applications, it is necessary to rediscover and exploit OAM. Here we propose a novel high-order OVL (HO-OVL) that combines the phase multiplication and the arbitrary mode-controllable techniques. TC on each OV in the lattice is up to 51, which generates sufficient OAM to manipulate microparticles. Thereafter, the entire lattice can be modulated to desirable arbitrary modes. Finally, yeast cells are trapped and rotated by the proposed HO-OVL. To the best of our knowledge, this is the first realization of the complex motion of microparticles via OVL. Thus, this work successfully exploits OAM on OVL, thereby revealing potential applications in particle manipulation and optical tweezers.

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Comparison of microparticle manipulating characteristics of canonical vortex beam and power-exponent-phase vortex beam

Journal of Modern Optics ◽

10.1080/09500340.2021.1889060 ◽

2021 ◽

pp. 1-9

Author(s):

Zhonghua Pei ◽

Sujuan Huang ◽

Yi Chen ◽

Cheng Yan

Keyword(s):

Power Exponent ◽

Vortex Beam

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ORIENTATING MANIPULATION OF CYLINDRICAL PARTICLES WITH OPTICAL TWEEZERS

Journal of Nonlinear Optical Physics & Materials ◽

10.1142/s021886350800438x ◽

2008 ◽

Vol 17 (04) ◽

pp. 387-394 ◽

Cited By ~ 1

Author(s):

XIUDONG SUN ◽

XUECONG LI ◽

JIANLONG ZHANG

Keyword(s):

Escherichia Coli ◽

Carbon Nanotubes ◽

Laser Beam ◽

Optical Tweezers ◽

Optical Trap ◽

Polarization Direction ◽

Beam Shape ◽

E Coli ◽

Potential Applications ◽

Cylindrical Particles

Orientating manipulations of cylindrical particles were performed by optical tweezers. Vertical and horizontal manipulations of Escherichia coli (E. coli) were carried out by changing the trapping depth and the focused laser beam shape. It was found that carbon nanotubes bundles (CNTBs) could be rotated in the linear polarized optical trap until it orientated its long axis along the linear polarization direction of the laser beam. However, E.coli could not be orientated in this way. Corresponding mechanisms were discussed based on the anisomeric electric characters of CNTBs. These orientation technologies of cylindrical objects with optical trap have potential applications in assembling nano-electric devices.

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Partially Coherent Imaging of a Straight-edged Object Associated with Periodic Structures of Acoustically Modified Spatial Coherence

Journal of Modern Optics ◽

10.1080/09500348714551071 ◽

1987 ◽

Vol 34 (9) ◽

pp. 1179-1192

Author(s):

Yoshihiro Ohtsuka

Keyword(s):

Periodic Structures ◽

Spatial Coherence ◽

Coherent Imaging ◽

Partially Coherent

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Microgels and Nanoparticles: Where Micro and Nano Go Hand in Hand

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2014-0578 ◽

2015 ◽

Vol 229 (1-2) ◽

Author(s):

Beatriz H. Juarez ◽

Luis M. Liz-Marzán

Keyword(s):

Magnetic Nanoparticles ◽

Optical Tweezers ◽

Hybrid System ◽

Inorganic Nanoparticles ◽

Stimuli Responsive ◽

Single Particles ◽

Nanoscale Systems ◽

Different Types ◽

Potential Applications ◽

Very High

AbstractThe integration of different types of materials in a single hybrid system allows the combination of multiple functionalities, which can even be used in conjunction with each other. This strategy has been exploited in nanoscale systems for the creation of so-called smart nanomaterials. Within this category, the combination of inorganic nanoparticles with stimuli-responsive microgels is of very high interest because of the wide variety of potential applications. We present here a short overview of this type of materials in which the nano- and micro-scales get nicely integrated, with a great potential to expand the range of technological applications. We focus mainly on the integration of metal nanoparticles, either by themselves or in combination with semiconductor and magnetic nanoparticles. Various examples of the synergic properties that can be obtained are described, as well as the possibility to extract useful information when optical tweezers are used to manipulate single particles. We expect that this review will stimulate additional research in this field.

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Transparent Metasurface for Generating Microwave Vortex Beams with Cross-Polarization Conversion

Materials ◽

10.3390/ma11122448 ◽

2018 ◽

Vol 11 (12) ◽

pp. 2448 ◽

Cited By ~ 10

Author(s):

Hongyu Shi ◽

Luyi Wang ◽

Mengran Zhao ◽

Juan Chen ◽

Anxue Zhang ◽

...

Keyword(s):

Transmission Loss ◽

Phase Distribution ◽

Polarization Conversion ◽

Vortex Beam ◽

Cross Polarization ◽

Measurement Results ◽

Vortex Beams ◽

Simulation Results ◽

Polarization Level ◽

Transmission Phase

In this paper, metasurfaces with both cross-polarization conversion and vortex beam-generating are proposed. The proposed finite metasurface designs are able to change the polarization of incident electromagnetic (EM) waves to its cross-polarization. In addition, they also can modulate the incidences into beams carrying orbital angular momentum (OAM) with different orders ( l = + 1 , l = + 2 , l = − 1 and l = − 2 ) by applying corresponding transmission phase distribution schemes on the metasurface aperture. The generated vortex beams are at 5.14 GHz. The transmission loss is lower than 0.5 dB while the co-polarization level is −10 dB compared to the cross-polarization level. The measurement results confirmed the simulation results and verified the properties of the proposed designs.

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