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arXiv · 2405.11462

Exciton polariton critical non-Hermitian skin effect with spin-momentum-locked gains

Xingran Xu·Lingyu Tian·Zhiyuan An·Qihua Xiong·Sanjib Ghosh
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Abstract

The critical skin effect, an intriguing phenomenon in non-Hermitian systems, displays sensitivity to system size and manifests distinct dynamical behaviors. In this work, we propose a novel scheme to achieve the critical non-Hermitian skin effect of exciton polaritons in an elongated microcavity system. We show that by utilising longitudinal-transverse spin splitting and spin-momentum-locked gain, a critical non-Hermitian skin effect can be achieved in a continuous system without the need of an underlying lattice. We find that a phase transition can be induced by changing the cavity detuning with respect to the exciton energy. We identify a measurable order parameter associated with this phase transition and demonstrate the corresponding critical behavior. Our work offers a flexible approach to manipulate non-Hermitian phases of exciton polaritons, thereby expanding the potential applications of polaritonic devices.

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Xingran Xu, Lingyu Tian, Zhiyuan An, Qihua Xiong, Sanjib Ghosh. 2024-05-19. Exciton polariton critical non-Hermitian skin effect with spin-momentum-locked gains. https://arxiv.org/abs/2405.11462

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