Dissipationless states in spin-boson systems

Benjamin Fain, S. H. Lin

Milena Grifoni, Elisabetta Paladino, U. Weiss

Andrzej Syrwid, Emil Blomquist, Egor S. Babaev

Dissipationless flows in single-component superfluids have a significant degree of universality. In ^{4}He, the dissipationless mass flow occurs with a superfluid velocity determined by the gradient of the superfluid phase. However, in interacting superfluid mixtures, principally new effects appear. In this Letter, we demonstrate a new kind of dissipationless phenomenon arising in mixtures of interacting bosons in optical lattices. We point out that for a particular class of optical lattices, bosons condense in a state where one of the components' superflow results in dissipationless mass flow of the other component, in a direction different from either of the components' superfluid velocities. The free-energy density of these systems contains a vector productlike interaction of superfluid velocities, producing the dissipationless noncollinear entrainment. The effect represents a superfluid counterpart of the Spin Hall effect.

Kevin Ingersent, Alper Duru

Han‐Jie Zhu, Guofeng Zhang, Lin Zhuang +1 more

We investigate the universal dissipationless dynamics of Gaussian continuous-variable systems in the presence of a band-gapped bosonic environment. Our results show that environmental band gaps can induce localized modes, which give rise to the dissipationless dynamics where the system behaves as free oscillators instead of experiencing a full decay in the long-time limit. We present a complete characterization of localized modes and show the existence of the critical system-environment coupling. Beyond the critical values, localized modes can be produced, and the system dynamics become dissipationless. This novel dynamics can be utilized to overcome the environmental noises and protect the quantum resources in the continuous-variable quantum information.

Ulrich Weiß, Maura Sassetti