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arXiv · 1610.06891

Phase sensing beyond the standard quantum limit with a truncated SU(1,1) interferometer

Brian E. Anderson·Prasoon Gupta·Bonnie L. Schmittberger·Travis Horrom·Carla Hermann-Avigliano·Kevin M. Jones·Paul D. Lett
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Abstract

An SU(1,1) interferometer replaces the beamsplitters in a Mach-Zehnder interferometer with nonlinear interactions and offers the potential of achieving high phase sensitivity in applications with low optical powers. We present a novel variation in which the second nonlinear interaction is replaced with balanced homodyne detection. The phase-sensing quantum state is a two-mode squeezed state produced by seeded four-wave-mixing in Rb vapor. Measurements as a function of operating point show that even with $\approx35~\%$ loss this device can surpass the standard quantum limit by 4~dB.

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Brian E. Anderson, Prasoon Gupta, Bonnie L. Schmittberger, Travis Horrom, Carla Hermann-Avigliano, Kevin M. Jones, Paul D. Lett. 2016-10-21. Phase sensing beyond the standard quantum limit with a truncated SU(1,1) interferometer. https://doi.org/10.1364/optica.4.000752

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