# Periodic mean-field solutions and the spectra of discrete bosonic fields: Trace formula for Bose-Hubbard models.

@article{Engl2015PeriodicMS, title={Periodic mean-field solutions and the spectra of discrete bosonic fields: Trace formula for Bose-Hubbard models.}, author={Thomas Engl and Juan Diego Urbina and Klaus Richter}, journal={Physical review. E, Statistical, nonlinear, and soft matter physics}, year={2015}, volume={92 6}, pages={ 062907 } }

- Published in Physical review. E, Statistical, nonlinear, and…2015
DOI:10.1103/PhysRevE.92.062907

We consider the many-body spectra of interacting bosonic quantum fields on a lattice in the semiclassical limit of large particle number N. We show that the many-body density of states can be expressed as a coherent sum over oscillating long-wavelength contributions given by periodic, nonperturbative solutions of the, typically nonlinear, wave equation of the classical (mean-field) limit. To this end, we construct the semiclassical approximation for both the smooth and oscillatory parts of the… CONTINUE READING