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arXiv · 1903.01017

Non-Hermitian dynamics without dissipation in quantum systems

Yu-Xin Wang·A. A. Clerk
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Abstract

Models based on non-Hermitian Hamiltonians can exhibit a range of surprising and potentially useful phenomena. Physical realizations typically involve couplings to sources of incoherent gain and loss; this is problematic in quantum settings, because of the unavoidable fluctuations associated with this dissipation. Here, we present several routes for obtaining unconditional non-Hermitian dynamics in non-dissipative quantum systems. We exploit the fact that quadratic bosonic Hamiltonians that do not conserve particle number give rise to non-Hermitian dynamical matrices. We discuss the nature of these mappings from non-Hermitian to Hermitian Hamiltonians, and explore applications to quantum sensing, entanglement dynamics and topological band theory. The systems we discuss could be realized in a variety of photonic and phononic platforms using the ubiquitous resource of parametric driving.

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Yu-Xin Wang, A. A. Clerk. 2019-03-03. Non-Hermitian dynamics without dissipation in quantum systems. https://doi.org/10.1103/physreva.99.063834

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