Excitation Spectra and Hard-core Thermodynamics of Bosonic Atoms In Double Well Optical Lattices

TL;DR

This paper introduces a coupled representation for bosonic atoms in double well optical lattices, analyzing their excitation spectra and thermodynamics, emphasizing the importance of hard-core bosonic statistics for accurate finite-temperature descriptions.

Contribution

It presents a novel coupled representation for bosonic atoms in double well lattices and highlights the significance of hard-core statistics in their thermodynamic analysis.

Findings

Excitation spectra are described by pseudo particles for doubly occupied and empty wells.

Hard-core bosonic statistics are essential for accurate finite-temperature properties.

Temperature dependence of particle numbers and heat capacity shows clear hard-core features.

Abstract

A general coupled representation is proposed for bosonic atoms in double well optical lattices. Based on such a representation, we investigate the excitation spectra and thermodynamics of bosonic atoms in the optical lattices. We find excitation spectra of the double well system with filling factor equal to one can be described by simultaneous excitations composed of pseudo particles corresponding to doubly occupied and empty double wells. It is demonstrated that hard-core bosonic statistics must be taken into account in order to properly describe the equilibrium properties at finite temperatures. For this we calculate the temperature dependence curves of particle numbers and heat capacity, in which the hard-core features are clearly shown. At last, the cases with filling factors unequal to one are also briefly discussed.