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arXiv · 2310.10377

Direct measurement of coherent light proportion from a practical laser source

Xi Jie Yeo·Eva Ernst·Alvin Leow·Jaesuk Hwang·Lijiong Shen·Christian Kurtsiefer·Peng Kian Tan
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Abstract

We present a technique to estimate the proportion of coherent emission in the light emitted by a practical laser source without spectral filtering. The technique is based on measuring interferometric photon correlations between the output ports of an asymmetric Mach-Zehnder interferometer. With this, we characterize the fraction of coherent emission in the light emitted by a laser diode when transiting through the lasing threshold.

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Xi Jie Yeo, Eva Ernst, Alvin Leow, Jaesuk Hwang, Lijiong Shen, Christian Kurtsiefer, Peng Kian Tan. 2023-10-16. Direct measurement of coherent light proportion from a practical laser source. https://doi.org/10.1103/physreva.109.013706

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