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arXiv · 2008.04084

Driven quadrature and spin squeezing in a cavity-coupled ensemble of two-level states

Haitham A. R. El-Ella
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Abstract

The generated magnitude of quadrature squeezing in a cavity-coupled ensemble, which is continuously driven using a coherent off-axis field, is theoretically explored. Using a truncated set of equations-of-motion derived from a Dicke Hamiltonian, steady-state quadrature squeezing of the cavity field is numerically calculated to approach a limit of -3 dB, while frequency-modulated quadrature squeezing approaches a limit of -14 dB, in the absence of pure-dephasing, and as a function of the ensemble's size and detuning. The impact of pure-dephasing on steady-state quadrature squeezing is shown to be mitigated by increased detuning of the driving field, while frequency-modulated squeezing is only shielded in a regime where the cumulative coupling and driving rates are in excess of the pure-dephasing rate. Spin-squeezed entanglement is also calculated to occur simultaneously with weakly-driven frequency-modulated quadrature squeezing.

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Haitham A. R. El-Ella. 2021-02-03. Driven quadrature and spin squeezing in a cavity-coupled ensemble of two-level states. https://doi.org/10.1103/physreva.103.023701

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