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arXiv · 1107.4256

PT symmetry and spontaneous symmetry breaking in a microwave billiard

S. Bittner·B. Dietz·U. Guenther·H. L. Harney·M. Miski-Oglu·A. Richter·F. Schaefer
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Abstract

We demonstrate the presence of parity-time (PT) symmetry for the non-Hermitian two-state Hamiltonian of a dissipative microwave billiard in the vicinity of an exceptional point (EP). The shape of the billiard depends on two parameters. The Hamiltonian is determined from the measured resonance spectrum on a fine grid in the parameter plane. After applying a purely imaginary diagonal shift to the Hamiltonian, its eigenvalues are either real or complex conjugate on a curve, which passes through the EP. An appropriate basis choice reveals its PT symmetry. Spontaneous symmetry breaking occurs at the EP.

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S. Bittner, B. Dietz, U. Guenther, H. L. Harney, M. Miski-Oglu, A. Richter, F. Schaefer. 2011-07-21. PT symmetry and spontaneous symmetry breaking in a microwave billiard. https://doi.org/10.1103/physrevlett.108.024101

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