Low-energy quantum dynamics of atoms at defects. Interstitial oxygen in silicon
Abstract
The problem of the low-energy highly-anharmonic quantum dynamics of isolated impurities in solids is addressed by using path-integral Monte Carlo simulations. Interstitial oxygen in silicon is studied as a prototypical example showing such a behavior. The assignment of a "geometry" to the defect is discussed. Depending on the potential (or on the impurity mass), there is a "classical" regime, where the maximum probability-density for the oxygen nucleus is at the potential minimum. There is another regime, associated to highly anharmonic potentials, where this is not the case. Both regimes are separated by a sharp transition. Also, the decoupling of the many-nuclei problem into a one-body Hamiltonian to describe the low-energy dynamics is studied. The adiabatic potential obtained from the relaxation of all the other degrees of freedom at each value of the coordinate associated to the low-energy motion, gives the best approximation to the full many-nuclei problem.
Keywords
Cite
@article{arxiv.cond-mat/9607115,
title = {Low-energy quantum dynamics of atoms at defects. Interstitial oxygen in silicon},
author = {Rafael Ramirez and Carlos P. Herrero and Emilio Artacho and Felix Yndurain},
journal= {arXiv preprint arXiv:cond-mat/9607115},
year = {2009}
}
Comments
RevTeX, 6 pages plus 4 figures (all the figures were not accesible before)