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arXiv 0910.4055cond-mat.stat-mech
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量子Ising自旋链突然猝灭后的扭结密度

Density of kinks after a sudden quench in the quantum Ising spin chain

Sei Suzuki, Davide Rossini, Giuseppe E. Santoro

摘要:

我们研究了自旋为1/2的量子Ising自旋链在横场强度突然猝灭后的扭结密度随时间的演化,发现它弛豫到一个依赖于横场初始值和最终值的值,并具有振荡的幂律衰减.我们提供了分析估计的长时间行为和完全放松后达到的渐近值,并讨论量子临界在淬火动力学中的作用。我们表明,在临界点的动力学,扭结淬火后的剩余密度可以描述由平衡统计力学在一个有限的温度决定的淬火后的状态的能量。另一方面,在临界状态之外,它不会表现出热化。

英文摘要:

We investigate the time evolution of the density of kinks in the spin-1/2 quantum Ising spin chain after a sudden quench in the transverse field strength, and find that it relaxes to a value which depends on the initial and the final values of the transverse field, with an oscillating power-law decay. We provide analytical estimates of the long-time behavior and of the asymptotic value reached after complete relaxation, and discuss the role of quantum criticality in the quench dynamics. We show that, for a dynamics at the critical point, the residual density of kinks after the quench can be described by equilibrium statistical mechanics at a finite temperature dictated by the energy of the state after the quench. On the other hand, outside of criticality it does not exhibit thermalization.

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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