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arXiv quant-ph/0005029quant-ph
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量子退相干与随机极限下的Glauber动力学

Quantum decoherence and the Glauber dynamics from the Stochastic limit

L. Accardi, S. V. Kozyrev

摘要:

研究了玻色场耦合量子系统的退相干效应。随机黄金法则的一个应用表明,在随机极限下,这样一个系统的动力学由一个量子随机微分方程描述。相应的主方程描述了系统向平衡态的收敛。特别地,它预测系统密度矩阵的非对角矩阵元素的指数阻尼,此外,一般系统的这些元素将至少衰减为\exp(-tN{kT \over \hbar }),其中N是系统中的粒子数。作为所述技术的应用,给出了从第一原理(即从哈密顿描述开始)导出用于自旋系统的Glauber动力学的量子扩展。

英文摘要:

The effects of decoherence for quantum system coupled with a bosonic field are investigated. An application of the stochastic golden rule shows that in the stochastic limit the dynamics of such a system is described by a quantum stochastic differential equation. The corresponding master equation describes convergence of a system to equilibrium. In particular it predicts exponential damping for off-diagonal matrix elements of the system density matrix, moreover these elements for a generic system will decay at least as \exp(-tN{kT\over\hbar}), where N is a number of particles in the system. As an application of the described technique a derivation from first principles (i.e. starting from a Hamiltonian description) of a quantum extension of the Glauber dynamics for systems of spins is given.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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