A simple renormalization group approximation of the groundstate properties of interacting bosonic systems
Abstract
We present a new, simple renormalization group method of investigating groundstate properties of interacting bosonic systems. Our method reduces the number of particles in a system, which makes numerical calculations possible for large systems. It is conceptually simple and easy to implement, and allows to investigate the properties unavailable through mean field approximations, such as one- and two-particle reduced density matrices of the groundstate. As an example, we model a weakly interacting 1D Bose gas in a harmonic trap. Compared to the mean-field Gross-Pitaevskii approximation, our method provides a more accurate description of the groundstate one-particle density matrix. We have also obtained the Hall-Post lower bounds for the groundstate energy of the gas. All results have been obtained by the straightforward numerical diagonalization of the Hamiltonian matrix.
Keywords
Cite
@article{arxiv.cond-mat/0510436,
title = {A simple renormalization group approximation of the groundstate properties of interacting bosonic systems},
author = {Roman Werpachowski and Jerzy Kijowski},
journal= {arXiv preprint arXiv:cond-mat/0510436},
year = {2013}
}
Comments
RevTex 4, 12 figures (revised and updated); to appear in Physical Review A