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arXiv · 2411.08965

Emerging Non-Hermitian Topology in a Chiral Driven-Dissipative Bose-Hubbard Model

Laszlo Rassaert·Tomás Ramos·Tommaso Roscilde·Diego Porras
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Abstract

We introduce a driven-dissipative Bose-Hubbard chain describing coupled lossy photonic modes, in which time-reversal symmetry is broken by a coherent drive with a uniform phase gradient. We investigate this model by means of a Gaussian variational ansatz and numerically prove that the steady-state solution is stabilized by an inhomogeneous profile of the driving amplitude, which damps out boundary effects. Our calculations unveil a non-equilibrium phase diagram showing low- and high-density phases for photons separated by a phase coexistence region in which the system exhibits the phenomenon of topological amplification and is characterized by a finite non-Hermitian winding number. Our work shows the emergence of non-Hermitian topological phases in an interacting model that can be naturally implemented with superconducting circuits.

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Laszlo Rassaert, Tomás Ramos, Tommaso Roscilde, Diego Porras. 2024-11-13. Emerging Non-Hermitian Topology in a Chiral Driven-Dissipative Bose-Hubbard Model. https://arxiv.org/abs/2411.08965

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