arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1301.0183cond-mat.mes-hallphysics.comp-ph
收藏

规范不变电流连续的微观交流量子输运理论

A gauge-invariant and current-continuous microscopic ac quantum transport theory

JianQiao Zhang, ZhenYu Yin, Xiao Zheng, ChiYung Yam, GuanHua Chen

摘要:

精确的交流量子输运理论一直是人们的共识,直到最近的一些工作挑战了传统的智慧。基于含时量子输运的非平衡格林函数理论,导出了满足规范不变性和电流连续性的动态导纳表达式,阐明了该领域的关键概念.利用第一性原理计算,计算了碳纳米管器件在随时间变化的偏压作用下的瞬态电流,验证了该方法的有效性.此外,以前被广泛接受的动态导纳的表达式,只有当设备是一个完美的导体在特定的电位恢复。

英文摘要:

There had been consensus on what the accurate ac quantum transport theory was until some recent works challenged the conventional wisdom. Basing on the non-equilibrium Green's function formalism for time-dependent quantum transport, we derive an expression for the dynamic admittance that satisfies gauge invariance and current continuity, and clarify the key concept in the field. The validity of our now formalism is verified by first-principles calculation of the transient current through a carbon-nanotube-based device under the time-dependent bias voltage. Moreover, the previously well-accepted expression for dynamic admittance is recovered only when the device is a perfect conductor at a specific potential.

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。

↑