Time-evolution stability of order parameters and phase diagrams of bosons on optical lattice

TL;DR

This paper investigates the stability over time of order parameters in bosonic systems on optical lattices, revealing how stability criteria shape phase diagrams and uncovering a pre-pairing mechanism akin to high-temperature superconductors.

Contribution

It introduces a stability-based approach to analyze phase diagrams of bosons on optical lattices, including multi-component systems, linking to phenomena in high-temperature superconductivity.

Findings

Stability of order parameters determines phase diagram structure.

Molecular superfluid phase emerges at a critical inter-species interaction.

Preformed molecules in atomic superfluid resemble high-Tc superconductor mechanisms.

Abstract

Stemming from the Heisenberg equations of motion, we study the time-evolution stability of the order parameters for the cold atoms on optical lattices. The requirement of this stability of the order parameters endows the phase diagram with a fruitful structure in the superfluid phase. For the one-component Bose-Hubbard model, we see that this stability of order parameter leads to a physically receivable phase diagram. For two-component bosons, we show that the molecules are preformed in the atomic superfluid and then condenses into a molecular superfluid phase at a critical repulsive inter-species interaction, which resembles the pre-pairing mechanism in high $T_c$ superconductor of Cu-O cuprates.