Quantum phases and transitions of bosons on a comb lattice

TL;DR

This paper investigates the quantum phases and phase transitions of interacting bosons on a comb lattice, revealing a rich phase diagram with Mott insulator, Luttinger liquids, and superfluid phases, relevant for condensed matter and cold-atom systems.

Contribution

It provides a detailed phase diagram of bosons on a comb lattice, identifying novel phases and transitions influenced by lattice geometry and interactions.

Findings

Identification of Mott-insulator, Luttinger liquids, and superfluid phases.

Mapping of phase diagram based on hopping amplitudes, interactions, and chemical potential.

Potential experimental realizations in condensed matter and cold-atom systems.

Abstract

Motivated to elucidate the nature of quantum phases and their criticality when entangled with a correlated quantum bath, we study interacting bosons on a "comb lattice" -- a one-dimensional backbone (system) coupled at its sites to otherwise independent one-dimensional "teeth" chains (bath). We map out the corresponding phase diagram, detailing the nature of the phases and phase transitions. Controlled by the backbone and teeth hopping amplitudes, on-site interaction and chemical potential, phases include a Mott-insulator (MI), backbone (LLb) and teeth (LLp) Luttinger liquids, and the long-range ordered incoherent superfluid (iSF). We explore their properties and potential realizations in condensed matter and cold-atom experiments and simulations.