Stochastic Description of Quantum Dissipative Dynamics
| 主 题 | Stochastic Description of Quantum Dissipative Dynamics |
| 报告人 | 邵久书（北京师范大学化学公司） |
| 时 间 | 2013年12月3日 16:00-17:00 |
| 地 点 | 理科一号楼1114室 |
| 摘 要 |
Upon employing the Hubbard-Stratonovich transformation or Ito calculus as well as the Girsanov transformation, the quantum dynamics of a dissipative system described by a system-plus-bath model is shown to satisfy a stochastic Liouville equation that might be regarded as the quantum analogue to the traditional Langevin equation.
The stochastic formulation can be used as a theoretical tool for deriving master equations for specific systems or developing approximations. It can also be employed as a practical technique for simulating dissipative dynamics numerically via a direct implementation or transforming to a deterministic algorithm a la hierarchical equations. It has been demonstrated that a mixed random-deterministic scheme taking both advantages of the random and deterministic treatments allows for the calculation of the zero-temperature dynamics of the dissipative two-state system with Ohmic dissipation. It is observed that for strong dissipation the population in the localized state obeys a simple rate dynamics and the time scale is proportional to the reciprocal of the cutoff frequency.
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