We propose an effective phonon treatment in one dimensional momentum-conserved lattice system with asymmetric interparticle interaction potentials. Our strategy is to divide the potential into two segments by the zero-potential point, and then approximate them by piecewise harmonic potentials with effective force constants k~L and k~R respectively. The effective phonons can then be well described by ωc=2(k~L+k~R). The numerical verifications show that this treatment works very well.
@article{arxiv.1511.00551,
title = {Effective phonon treatment of asymmetric interparticle interaction potentials},
author = {Weichen Fu and Hong Zhao},
journal= {arXiv preprint arXiv:1511.00551},
year = {2015}
}