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arXiv · 1806.10795

Origin of third order exceptional singularities and its signature in successive state conversion

Sayan Bhattacherjee·Arnab Laha·Somnath Ghosh
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Abstract

We report an open three-state perturbed system with quasi-statically varying Hamiltonian depending on the topological parameters. The effective system hosts two second order exceptional points (EP2s). Here a third order exceptional point (EP3) is explored with simultaneous encirclement of two EP2s by adiabatic variation of topological parameters. We study the robust successive state-exchange around the EP3. Applying adiabatic theorem, we estimate the evolution of total phase accumulated by each state during encirclement; where interestingly, the state-common to the pairs of coupled state picks up three times phase shift of 2{\pi}. Such an exclusively reported scheme can be exploited in potential applications of exceptional points, manipulating fewer topological parameters in various non-Hermitian systems.

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Sayan Bhattacherjee, Arnab Laha, Somnath Ghosh. 2018-06-28. Origin of third order exceptional singularities and its signature in successive state conversion. https://arxiv.org/abs/1806.10795

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