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arXiv · 1805.12557

Phase-dependent chiral transport and effective non-Hermitian dynamics in a bosonic Kitaev-Majorana chain

Alexander McDonald·T. Pereg-Barnea·A. A. Clerk
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Abstract

We study a 1D chain of non-interacting bosonic cavities which are subject to nearest-neighbour parametric driving. With a suitable choice of drive phases, this model is strongly analogous to the celebrated Kitaev chain model of a 1D p-wave superconductor. The system exhibits phase-dependent chirality: photons propagate and are amplified in a direction that is determined by the phase of the initial drive or excitation. Further, we find a drastic sensitivity to boundary conditions: for a range of parameters, the boundary-less system has only delocalized, dynamically unstable modes, while a finite open chain is described by localized, dynamically stable modes. While our model is described by a Hermitian Hamiltonian, we show that it has a surprising connection to non-Hermitian asymmetric-hopping models.

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Alexander McDonald, T. Pereg-Barnea, A. A. Clerk. 2018-05-31. Phase-dependent chiral transport and effective non-Hermitian dynamics in a bosonic Kitaev-Majorana chain. https://doi.org/10.1103/physrevx.8.041031

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