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Photonics

A Simplified Laser System for Atom Interferometry Based on a Free-Space EOM

Bin Wu, Yingpeng Zhao, Bing Cheng, Can Zhang, Dianrong Li, Dong Zhu, Yazhou Yue, Jun Li, Kaijun Zhang, Qiang Lin, Kanxing Weng

Published Apr 28, 2022• 6 citations

Abstract

In this paper, a compact laser system for 87Rb atom interferometry based on only one free-space electro-optic modulator (EOM) was realized, where repumping and Raman beams were generated with a free-space EOM. In addition, this laser system does not require a laser amplifier compared to fibered EOM since fibered EOM cannot transmit high-power lasers. However, due to the narrow modulation linewidth of free-space EOM, it is impossible to obtain the frequencies of repumping and Raman beams separately, which would lead to some complicated effects. Therefore, a theoretical analysis was carried out to solve this problem, and a new frequency scheme for AI is proposed. For the experiment, the laser system of AI was built up. Moreover, the atomic interference fringes were obtained with a contrast of 20.7% (T = 60 ms) and the fitted phase resolution is approximately 1.25 mrad. The presented laser system could provide a new solution for compact AI systems in the future.

DOI: 10.3390/photonics9050301

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We produced two Raman-laser beams with a frequency offset of 6.834GHz by injection-locking of a master diode-laser to a slave diode-laser. The master laser was phase-modulated at 6.834 GHz with an Electro-Optic Modulator and then injected into the slave laser that was oscillating around one of the side-bands. The relative linewidth of the two lasers was less than 1 Hz. Utilizing these laser beams, we realized the coherent manipulation of atomic wave packets in a Mach-Zehnder type atom interferometry.