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arXiv · 1501.03279

Magnetic-field-induced rotation of light with orbital angular momentum

Shuai Shi·Dong-Sheng Ding·Zhi-Yuan Zhou·Yan Li·Wei Zhang·Bao-Sen Shi
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Abstract

Light carrying orbital angular momentum (OAM) has attractive applications in the fields of precise optical measurements and high capacity optical communications. We study the rotation of a light beam propagating in warm 87Rb atomic vapor using a method based on magnetic-field-induced circular birefringence. The dependence of the rotation angle on the magnetic field makes it appropriate for weak magnetic field measurements. We quote a detailed theoretical description that agrees well with the experimental observations. The experiment shown here provides a method to measure the magnetic field intensity precisely and expands the application of OAM-carrying light. This technique has advantage in measurement of magnetic field weaker than 0.5 Gauss, and the precision we achieved is 0.8 mGauss.

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Shuai Shi, Dong-Sheng Ding, Zhi-Yuan Zhou, Yan Li, Wei Zhang, Bao-Sen Shi. 2015-01-14. Magnetic-field-induced rotation of light with orbital angular momentum. https://doi.org/10.1063/1.4923446

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