Ground-states of spin-1 bosons in asymmetric double-wells

TL;DR

This paper explores the ground states of spin-1 bosons in a double-well potential, analyzing how spin-dependent interactions and tunneling influence state transitions, with a focus on fidelity and occupation number changes.

Contribution

It introduces a detailed analysis of spin-1 boson ground states in asymmetric double-wells using fidelity and occupation metrics, extending understanding beyond two-particle systems.

Findings

Identification of critical parameters for ground state changes

Characterization of spin and occupation correlations

Extension of analysis to larger particle numbers

Abstract

In this work we investigate the different states of a system of spin-1 bosons in two potential wells connected by tunneling, with spin-dependent interaction. The model utilizes the well-known Bose-Hubbard Hamiltonian, adding a local interaction term that depends on the modulus of the total spin in a well, favoring a high- or low-spin state for different signs of the coupling constant. We employ the concept of fidelity to detect critical values of parameters for which the ground state undergoes significant changes. The nature of the states is investigated through evaluation of average occupation numbers in the wells and of spin correlations. A more detailed analysis is done for a two-particle system, but a discussion of the three-particle case and some results for larger numbers are also presented.