Bosonic many-body systems with topologically nontrivial phases subject to gain and loss

Abstract

Topological properties of physical systems are preserved under large variations in the system parameters and hence interesting for applications in communication networks and quantum computing. This work investigates the impact of dissipation on a class of one-dimensional bosonic systems, described by superlattice Bose-Hubbard models, that exhibit topologically nontrivial phases in the absence of dissipation. Gains and losses are modeled in two different frameworks (non-Hermitian PT-symmetric Hamiltonians and master equations in Lindblad form) and numerically investigated with variants of density matrix renormalization group methods. Empirically, both dissipative extensions give rise to similar effects when compared on different dissipative patterns. In the presence of strong local gain and loss, dissipative sites act as system boundaries that can induce edge states in the Hermitian subsystems.