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arXiv · 2112.01382

Shot-Noise Limited Homodyne Detection for MHz Quantum Light Characterisation in the 2 {\mu}m Band

Jake Biele·Joel F. Tasker·Joshua W. Silverstone·Jonathan C. F. Matthews
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Abstract

Characterising quantum states of light in the 2 ${\mu}m$ band requires high-performance shot-noise limited detectors. Here, we present the characterisation of a homodyne detector that we use to observe vacuum shot-noise via homodyne measurement with a 2.07 ${\mu}m$ pulsed mode-locked laser. The device is designed primarily for pulsed illumination. It has a 3 dB bandwidth of 13.2 MHz, total conversion efficiency of 58% at 2.07 ${\mu}m$ and a common-mode rejection ratio of 48 dB at 39.5 MHz. The detector begins to saturate at 1.8 mW with 9 dB of shot-noise clearance at 5 MHz. This demonstration enables the characterisation of megahertz-quantum optical behaviour in the 2 ${\mu}m$ band.

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Jake Biele, Joel F. Tasker, Joshua W. Silverstone, Jonathan C. F. Matthews. 2021-12-02. Shot-Noise Limited Homodyne Detection for MHz Quantum Light Characterisation in the 2 {\mu}m Band. https://doi.org/10.1364/oe.450217

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