One- and two-atom states in a rotating ring lattice

TL;DR

This paper investigates the quantum states of one and two atoms in a rotating ring lattice using a Hubbard model, revealing how rotation influences atom states and enables control over their configurations.

Contribution

The paper develops a detailed Hubbard model for rotating ring lattices, elucidating how rotation speed affects atom states and enabling state control.

Findings

One-atom ground state can be degenerate and depend on lattice parameters.

Rotation speed variation can control atom states and induce peculiar velocity behaviors.

Adiabatic rotation can confine two atoms to the same lattice site.

Abstract

We study the states of one and two atoms in a rotating ring lattice in a Hubbard type tight-binding model. The model is developed carefully from basic principles in order to properly identify the physical observables. The one-particle ground state may be degenerate and represent a finite flow velocity depending on the parity of the number of lattice sites, the sign of the tunneling matrix element, and the rotation speed of the lattice. Variation of the rotation speed may be used to control one-atom states, and leads to peculiar behaviors such as wildly different phase and group velocities for an atom. Adiabatic variation of the rotation speed of the lattice may also be used to control the state of a two-atom lattice dimer. For instance, at a suitably chosen rotation speed both atoms are confined to the same lattice site.