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arXiv · 1006.2540

Photon generation in an electromagnetic cavity with a time-dependent boundary

C. M. Wilson·T. Duty·M. Sandberg·F. Persson·V. Shumeiko·P. Delsing
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Abstract

We report the observation of photon generation in a microwave cavity with a time-dependent boundary condition. Our system is a microfabricated quarter-wave coplanar waveguide cavity. The electrical length of the cavity is varied using the tunable inductance of a superconducting quantum interference device. It is measured in the quantum regime, where the temperature is significantly less than the resonance frequency (~ 5 GHz). When the length is modulated at approximately twice the static resonance frequency, spontaneous oscillations of the cavity field are observed. Time-resolved measurements of the dynamical state of the cavity show multiple stable states. The behavior is well described by theory. Connections to the dynamical Casimir effect are discussed.

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C. M. Wilson, T. Duty, M. Sandberg, F. Persson, V. Shumeiko, P. Delsing. 2010-06-13. Photon generation in an electromagnetic cavity with a time-dependent boundary. https://doi.org/10.1103/physrevlett.105.233907

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