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Observation of a Chiral State in a Microwave Cavity

C. Dembowski·B. Dietz·H. -D. Graef·H. L. Harney·A. Heine·W. D. Heiss·A. Richter
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Abstract

A microwave experiment has been realized to measure the phase difference of the oscillating electric field at two points inside the cavity. The technique has been applied to a dissipative resonator which exhibits a singularity -- called exceptional point -- in its eigenvalue and eigenvector spectrum. At the singularity, two modes coalesce with a phase difference of $π/2 .$ We conclude that the state excited at the singularity has a definitiv chirality.

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C. Dembowski, B. Dietz, H. -D. Graef, H. L. Harney, A. Heine, W. D. Heiss, A. Richter. 2003-02-06. Observation of a Chiral State in a Microwave Cavity. https://doi.org/10.1103/physrevlett.90.034101

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