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Title: Spin polarization of {sup 87}Rb atoms with ultranarrow linewidth diode laser: Numerical simulation

Abstract

In order to polarize {sup 87}Rb vapor effectively with ultranarrow linewidth diode laser, we studied the polarization as a function of some parameters including buffer gas pressure and laser power. Moreover, we also discussed the methods which split or modulate the diode laser frequency so as to pump the two ground hyperfine levels efficiently. We obtained some useful results through numerical simulation. If the buffer gas pressure is so high that the hyperfine structure is unresolved, the polarization is insensitive to laser frequency at peak absorption point so frequency splitting and frequency modulation methods do not show improvement. At low pressure and laser power large enough, where the hyperfine structure is clearly resolved, frequency splitting and frequency modulation methods can increase polarization effectively. For laser diodes, frequency modulation is easily realized with current modulation, so this method is attractive since it does not add any other components in the pumping laser system.

Authors:
 [1];  [2];  [2]; ; ; ;  [1];  [2]
  1. College of OptoElectronic Science and Engineering, National University of Defense Technology, Changsha, 410073 (China)
  2. (China)
Publication Date:
OSTI Identifier:
22611401
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:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABSORPTION; BUFFERS; COMPUTERIZED SIMULATION; FREQUENCY MODULATION; HYPERFINE STRUCTURE; LASER RADIATION; OPTICAL PUMPING; POLARIZATION; RUBIDIUM 87; SPIN; SPIN ORIENTATION

Citation Formats

Wang, Z. G., Interdisciplinary Center of Quantum Information, National University of Defense Technology, Changsha, 410073, College of Science, National University of Defense Technology, Changsha, 410073, Jiang, Q. Y., Zhan, X., Chen, Y. D., Luo, H., E-mail: luohui.luo@163.com, and Interdisciplinary Center of Quantum Information, National University of Defense Technology, Changsha, 410073. Spin polarization of {sup 87}Rb atoms with ultranarrow linewidth diode laser: Numerical simulation. United States: N. p., 2016. Web. doi:10.1063/1.4961375.
Wang, Z. G., Interdisciplinary Center of Quantum Information, National University of Defense Technology, Changsha, 410073, College of Science, National University of Defense Technology, Changsha, 410073, Jiang, Q. Y., Zhan, X., Chen, Y. D., Luo, H., E-mail: luohui.luo@163.com, & Interdisciplinary Center of Quantum Information, National University of Defense Technology, Changsha, 410073. Spin polarization of {sup 87}Rb atoms with ultranarrow linewidth diode laser: Numerical simulation. United States. doi:10.1063/1.4961375.
Wang, Z. G., Interdisciplinary Center of Quantum Information, National University of Defense Technology, Changsha, 410073, College of Science, National University of Defense Technology, Changsha, 410073, Jiang, Q. Y., Zhan, X., Chen, Y. D., Luo, H., E-mail: luohui.luo@163.com, and Interdisciplinary Center of Quantum Information, National University of Defense Technology, Changsha, 410073. 2016. "Spin polarization of {sup 87}Rb atoms with ultranarrow linewidth diode laser: Numerical simulation". United States. doi:10.1063/1.4961375.
@article{osti_22611401,
title = {Spin polarization of {sup 87}Rb atoms with ultranarrow linewidth diode laser: Numerical simulation},
author = {Wang, Z. G. and Interdisciplinary Center of Quantum Information, National University of Defense Technology, Changsha, 410073 and College of Science, National University of Defense Technology, Changsha, 410073 and Jiang, Q. Y. and Zhan, X. and Chen, Y. D. and Luo, H., E-mail: luohui.luo@163.com and Interdisciplinary Center of Quantum Information, National University of Defense Technology, Changsha, 410073},
abstractNote = {In order to polarize {sup 87}Rb vapor effectively with ultranarrow linewidth diode laser, we studied the polarization as a function of some parameters including buffer gas pressure and laser power. Moreover, we also discussed the methods which split or modulate the diode laser frequency so as to pump the two ground hyperfine levels efficiently. We obtained some useful results through numerical simulation. If the buffer gas pressure is so high that the hyperfine structure is unresolved, the polarization is insensitive to laser frequency at peak absorption point so frequency splitting and frequency modulation methods do not show improvement. At low pressure and laser power large enough, where the hyperfine structure is clearly resolved, frequency splitting and frequency modulation methods can increase polarization effectively. For laser diodes, frequency modulation is easily realized with current modulation, so this method is attractive since it does not add any other components in the pumping laser system.},
doi = {10.1063/1.4961375},
journal = {AIP Advances},
number = 8,
volume = 6,
place = {United States},
year = 2016,
month = 8
}
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