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arXiv · 2003.12545

Quantum-Enhanced Fiber-Optic Gyroscopes Using Quadrature Squeezing and Continuous Variable Entanglement

Michael R Grace·Christos N. Gagatsos·Quntao Zhuang·Saikat Guha
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Abstract

We analyze a fiber-optic gyroscope design enhanced by the injection of quantum-optical squeezed vacuum into a fiber-based Sagnac interferometer. In the presence of fiber loss, we compute the maximum attainable enhancement over a classical, laser-driven fiber-optic gyroscope in terms of the angular velocity estimate variance from a homodyne measurement. We find a constant enhancement factor that depends on the degree of squeezing introduced into the system but has diminishing returns beyond $10$--$15$ dB of squeezing. Under a realistic constraint of fixed total fiber length, we show that segmenting the available fiber into multiple Sagnac interferometers fed with a multi-mode-entangled squeezed vacuum, thereby establishing quantum entanglement across the individual interferometers, improves the rotation estimation variance by a factor of $e\approx2.718$.

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Michael R Grace, Christos N. Gagatsos, Quntao Zhuang, Saikat Guha. 2020-03-27. Quantum-Enhanced Fiber-Optic Gyroscopes Using Quadrature Squeezing and Continuous Variable Entanglement. https://doi.org/10.1103/physrevapplied.14.034065

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