1207.3349 (H. C. Peñate-Rodriguez et al.)

A Langevin canonical approach to the dynamics of two level systems. I.
Populations and coherences    [PDF]

H. C. Peñate-Rodriguez, A. Dorta-Urra, P. Bargueno, G. Rojas-Lorenzo, S. Miret-Artes

A canonical framework for two-level systems coupled to a bath of harmonic oscillators is developed to extract, from a stochastic dynamics, the thermodynamic equilibrium values of both the population difference and coherences. The incoherent and coherent tunneling regimes are analyzed for an Ohmic environment from moderate-to-high temperatures. The corresponding numerical results issued from solving a non-linear coupled system are fitted to approximate path-integral analytical expressions in order to determine the different time scales governing both regimes.

View original: http://arxiv.org/abs/1207.3349