Observation of the First-Order Interference Fringes Beyond Coherence Length Employing Commercial Continuous-wave Multi-mode Laser Diode: A Sight of Two-photon Interference

Hongmin Liu

arXiv:2402.15041Feb 23, 20240 citations

arXiv:1910.10886 · Physical Review A

Implementation of a double-path multimode interferometer using a spinor Bose-Einstein condensate

Pengju Tang, Xiangyu Dong, Wenjun Zhang, Yunhong Li, Xuzong Chen, Xiaoji Zhou

Published Jan 13, 2020• 6 citations

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Abstract

DOI: 10.1103/physreva.101.013612

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Atom interferometry with high visibility is of high demand for precision measurements. Here, a parallel multicomponent interferometer is achieved by preparing a spin-2 Bose-Einstein condensate of

^{87}\mathrm{Rb}

atoms confined in a hybrid magneto-optical trap. After the preparation of a spinor Bose-Einstein condensate with spin degrees of freedom entangled, we observe four spatial interference patterns in each run of measurements corresponding to four hyperfine states we mainly populate in the experiment. The atomic populations in different Zeeman sublevels are made controllably using magnetic-field-pulse induced Majorana transitions. The spatial separation of atom cloud in different hyperfine states is reached by Stern-Gerlach momentum splitting. The high visibility of the interference fringes is reached by designing a proper overlap of the interfering wave packets. Due to uncontrollable phase accumulation in Majorana transitions, the phase of each individual spin is found to be subjected to unreproducible shift in multiple experimental runs. However, the relative phase across different spins is stable, paving a way towards noise-resilient multicomponent parallel interferometers.