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arXiv · 0905.4478

Observation of an exceptional point in a chaotic optical microcavity

Sang-Bum Lee·Juhee Yang·Songky Moon·Soo-Young Lee·Jeong-Bo Shim·Sang Wook Kim·Jai-Hyung Lee·Kyungwon An
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Abstract

We present spectroscopic observation of an exceptional point or the transition point between diabatic crossing and avoided crossing of neighboring quasi-eigenmodes in a chaotic optical microcavity with a large size parameter. The transition to the avoided crossing was impeded until the degree of deformation exceeded a threshold deformation owing to the system's openness also enhanced by the shape deformation. As a result, a singular topology was observed around the exceptional point on the eigenfrequency surfaces, resulting in fundamental inconsistency in mode labeling.

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Sang-Bum Lee, Juhee Yang, Songky Moon, Soo-Young Lee, Jeong-Bo Shim, Sang Wook Kim, Jai-Hyung Lee, Kyungwon An. 2009-05-27. Observation of an exceptional point in a chaotic optical microcavity. https://doi.org/10.1103/physrevlett.103.134101

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