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Title: Annular beam with segmented phase gradients

Abstract

An annular beam with a single uniform-intensity ring and multiple segments of phase gradients is proposed in this paper. Different from the conventional superposed vortices, such as the modulated optical vortices and the collinear superposition of multiple orbital angular momentum modes, the designed annular beam has a doughnut intensity distribution whose radius is independent of the phase distribution of the beam in the imaging plane. The phase distribution along the circumference of the doughnut beam can be segmented with different phase gradients. Similar to a vortex beam, the annular beam can also exert torques and rotate a trapped particle owing to the orbital angular momentum of the beam. As the beam possesses different phase gradients, the rotation velocity of the trapped particle can be varied along the circumference. The simulation and experimental results show that an annular beam with three segments of different phase gradients can rotate particles with controlled velocities. The beam has potential applications in optical trapping and optical information processing.

Authors:
;  [1];  [1];  [2]
  1. School of Physics and Electronics, Central South University, Changsha, Hunan 410083 (China)
  2. (China)
Publication Date:
OSTI Identifier:
22611381
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 6; Journal Issue: 8; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BEAMS; DESIGN; DISTRIBUTION; ORBITAL ANGULAR MOMENTUM; ROTATION; SIMULATION; TORQUE; TRAPPING; VORTICES

Citation Formats

Cheng, Shubo, Wu, Liang, Tao, Shaohua, E-mail: eshtao@csu.edu.cn, and Hunan Key Laboratory for Super-microstructure and Ultrafast Process, School of Physics and Electronics, Central South University, Changsha, Hunan 410083. Annular beam with segmented phase gradients. United States: N. p., 2016. Web. doi:10.1063/1.4962301.
Cheng, Shubo, Wu, Liang, Tao, Shaohua, E-mail: eshtao@csu.edu.cn, & Hunan Key Laboratory for Super-microstructure and Ultrafast Process, School of Physics and Electronics, Central South University, Changsha, Hunan 410083. Annular beam with segmented phase gradients. United States. doi:10.1063/1.4962301.
Cheng, Shubo, Wu, Liang, Tao, Shaohua, E-mail: eshtao@csu.edu.cn, and Hunan Key Laboratory for Super-microstructure and Ultrafast Process, School of Physics and Electronics, Central South University, Changsha, Hunan 410083. 2016. "Annular beam with segmented phase gradients". United States. doi:10.1063/1.4962301.
@article{osti_22611381,
title = {Annular beam with segmented phase gradients},
author = {Cheng, Shubo and Wu, Liang and Tao, Shaohua, E-mail: eshtao@csu.edu.cn and Hunan Key Laboratory for Super-microstructure and Ultrafast Process, School of Physics and Electronics, Central South University, Changsha, Hunan 410083},
abstractNote = {An annular beam with a single uniform-intensity ring and multiple segments of phase gradients is proposed in this paper. Different from the conventional superposed vortices, such as the modulated optical vortices and the collinear superposition of multiple orbital angular momentum modes, the designed annular beam has a doughnut intensity distribution whose radius is independent of the phase distribution of the beam in the imaging plane. The phase distribution along the circumference of the doughnut beam can be segmented with different phase gradients. Similar to a vortex beam, the annular beam can also exert torques and rotate a trapped particle owing to the orbital angular momentum of the beam. As the beam possesses different phase gradients, the rotation velocity of the trapped particle can be varied along the circumference. The simulation and experimental results show that an annular beam with three segments of different phase gradients can rotate particles with controlled velocities. The beam has potential applications in optical trapping and optical information processing.},
doi = {10.1063/1.4962301},
journal = {AIP Advances},
number = 8,
volume = 6,
place = {United States},
year = 2016,
month = 8
}
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