Dephasing by a continuous-time random walk process

作者：Packwood Daniel M^*; Tanimura Yoshitaka

来源：Physical Review E, 2012, 86(1): 011130.

DOI：10.1103/PhysRevE.86.011130

Stochastic treatments of magnetic resonance spectroscopy and optical spectroscopy require evaluations of functions such as < exp(i integral(t)(0) Q(s)ds)> where t is time, Q(s) is the value of a stochastic process at time s, and the angular brackets denote ensemble averaging. This paper gives an exact evaluation of these functions for the case where Q is a continuous-time random walk process. The continuous-time random walk describes an environment that undergoes slow steplike changes in time. It also has a well-defined Gaussian limit and so allows for non-Gaussian and Gaussian stochastic dynamics to be studied within a single framework. We apply the results to extract qubit-lattice interaction parameters from dephasing data of P-doped Si semiconductors (data collected elsewhere) and to calculate the two-dimensional spectrum of a three-level harmonic oscillator undergoing random frequency modulations.

• 出版日期2012-7-26