Superfluidity of spin-1 bosons in optical lattices

TL;DR

This paper demonstrates that superfluidity in spin-1 Bose atoms within optical lattices can be achieved and controlled by analyzing the excitation spectrum and critical velocities, which vary among spin components and depend on lattice parameters.

Contribution

It provides a theoretical analysis of superfluidity in spin-1 bosons in optical lattices using Bogliubov transformation, highlighting controllable critical velocities for different spin components.

Findings

Superfluidity can be realized in spin-1 Bose atoms in optical lattices.

Critical velocities differ among the three spin components.

Lattice parameters can be adjusted to control superfluid properties.

Abstract

In this paper we show that the superfluidity of cold spin--1 Bose atoms of weak interactions in an optical lattice can be realized according to the excitation energy spectrum which is derived by means of Bogliubov transformation. The characteristic of the superfluid-phase spectrum is explained explicitly in terms of the nonvanishing critical velocity, i.e., the Landau criterion. It is observed that critical velocities of superfluid are different for three spin components and, moreover, can be controlled by adjusting the lattice parameters in practical experiments to detect the superfluid phase.