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arXiv · 1605.08953

Parity-time symmetry under magnetic flux

L. Jin·Z. Song
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Abstract

We study a parity-time (PT) symmetric ring lattice, with one pair of balanced gain and loss located at opposite positions. The system remains PT-symmetric when threaded by a magnetic flux; however, the PT symmetry is sensitive to the magnetic flux, in the presence of a large balanced gain and loss, or in a large system. We find a threshold gain/loss, above which, any nontrivial magnetic flux breaks the PT symmetry. We obtain the maximally tolerable magnetic flux for the exact PT-symmetric phase, which is approximately linearly dependent on a weak gain/loss.

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L. Jin, Z. Song. 2016-05-29. Parity-time symmetry under magnetic flux. https://doi.org/10.1103/physreva.93.062110

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