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arXiv · 2011.04561

Universal conductance of a PT-symmetric Luttinger liquid after a quantum quench

Cătălin Paşcu Moca·Balázs Dóra
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Abstract

We study the non-equilibrium dynamics and transport of a PT-symmetric Luttinger liquid (LL) after an interaction quench. The system is prepared in domain wall initial state. After a quantum quench to spatially homogeneous, PT-symmetric LL, the domain wall develops into a flat central region that spreads out ballistically faster than the conventional Lieb-Robinson maximal speed. By evaluating the current inside the regular lightcone, we find a universal conductance $e^2/h$, insensitive to the strength of the PT-symmetric interaction. On the other hand, by repeating the very same time evolution with a hermitian LL Hamiltonian, the conductance is heavily renormalized by the hermitian interaction as $e^2/hK$ with $K$ the LL parameter. Our analytical results are tested numerically, confirming the universality of the conductance in the non-hermitian realm.

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Cătălin Paşcu Moca, Balázs Dóra. 2020-11-09. Universal conductance of a PT-symmetric Luttinger liquid after a quantum quench. https://doi.org/10.1103/physrevb.104.125124

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