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arXiv · 2306.14980

Observing Parity Time Symmetry Breaking in a Josephson Parametric Amplifier

Chandrashekhar Gaikwad·Daria Kowsari·Weijian Chen·Kater W. Murch
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Abstract

A coupled two-mode system with balanced gain and loss is a paradigmatic example of an open quantum system that can exhibit real spectra despite being described by a non-Hermitian Hamiltonian. We utilize a degenerate parametric amplifier operating in three-wave mixing mode to realize such a system of balanced gain and loss between the two quadrature modes of the amplifier. By examining the time-domain response of the amplifier, we observe a characteristic transition from real-to-imaginary energy eigenvalues associated with the Parity-Time-symmetry-breaking transition.

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Chandrashekhar Gaikwad, Daria Kowsari, Weijian Chen, Kater W. Murch. 2023-06-26. Observing Parity Time Symmetry Breaking in a Josephson Parametric Amplifier. https://doi.org/10.1103/physrevresearch.5.l042024

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