Self-organized topological insulator due to cavity-mediated correlated tunneling

Seminarium BEC

Titas

Chanda

Jagiellonian University

November 27, 2020 11:00 AM

Topological materials have potential applications for quantum technologies. Non-interacting topo- logical materials, such as e.g., topological insulators and superconductors, are classified by means of fundamental symmetry classes. It is instead only partially understood how interactions affect topological properties. Here, we discuss a model where topology emerges from the quantum in- terference between single-particle dynamics and global interactions. The system is composed by soft-core bosons that interact via global correlated hopping in a one-dimensional lattice. The onset of quantum interference leads to spontaneous breaking of the lattice translational symmetry, the corresponding phase resembles nontrivial states of the celebrated Su-Schriefer-Heeger model. Like the fermionic Peierls instability, the emerging quantum phase is a topological insulator and is found at half fillings (namely, when the number of sites is twice as large as the number of bosons). Nevertheless, here it arises from an interference phenomenon that has no known fermionic analog. We argue that these dynamics can be realized in existing experimental platforms, such as cavity quantum electrodynamics setups, where the topological features can be revealed in the light emitted by the resonator.