Achieving the Neel state in an optical lattice

TL;DR

This paper investigates how to experimentally realize the antiferromagnetic Neel state in a Hubbard model using ultracold fermionic atoms in an optical lattice, focusing on temperature and atom number constraints.

Contribution

It provides a theoretical analysis of the conditions needed to adiabatically reach the Neel state, considering fluctuations beyond mean-field theory.

Findings

Fluctuations significantly limit adiabatic preparation of the Neel state.

Initial temperature and atom number are critical for success.

Entropy considerations determine feasibility in three-dimensional lattices.

Abstract

We theoretically study the possibility of reaching the antiferromagnetic phase of the Hubbard model by starting from a normal gas of trapped fermionic atoms and adiabatically ramping up an optical lattice. Requirements on the initial temperature and the number of atoms are determined for a three dimensional square lattice by evaluating the Neel state entropy, taking into account fluctuations around the mean-field solution. We find that these fluctuations place important limitations on adiabatically reaching the Neel state.