arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1105.3145cond-mat.str-elcond-mat.quant-gasnucl-th
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莫特绝缘体中的非线性二重子产生-- Landau-Dykhne方法在可积模型中的应用

Non-linear doublon production in a Mott insulator --- Landau-Dykhne method applied to an integrable model

Takashi Oka

摘要:

在一维哈伯德模型中研究了强激光或静电电场作用下莫特绝缘体介质击穿时产生的双空穴对。两个非线性效应引起激励,即,多光子吸收和量子隧穿。当电场强度和光子能量改变时,两种机制之间会发生Keldysh交叉。用Landau-Dykhne方法结合Bethe近似解进行了解析计算,并与含时密度矩阵重整化群的计算结果进行了比较.使用这种方法,我们计算了所产生的双空穴对的分布函数,并表明它急剧变化,因为我们越过Keldysh交叉线。在计算了几种有代表性的一维莫特绝缘体的隧穿阈值后,提出了可能的实验检验,如量子隧穿区上Hubbard带的角分辨光电子能谱。我们还讨论了本理论与非线性量子电动力学中电子-正电子对产生的多体扩展的关系,称为Schwinger机制。

英文摘要:

Doublon-hole pair production which takes place during dielectric breakdown in a Mott insulator subject to a strong laser or a static electric field is studied in the one-dimensional Hubbard model. Two nonlinear effects cause the excitation, i.e., multi-photon absorption and quantum tunneling. Keldysh crossover between the two mechanisms occurs as the field strength and photon energy is changed. The calculation is done analytically by the Landau-Dykhne method in combination with the Bethe ansatz solution and the results are compared with those of the time dependent density matrix renormalization group. Using this method, we calculate distribution function of the generated doublon-hole pairs and show that it drastically changes as we cross the Keldysh crossover line. After calculating the tunneling threshold for several representative one-dimensional Mott insulators, possible experimental tests of the theory is proposed such as angle resolved photoemission spectroscopy of the upper Hubbard band in the quantum tunneling regime. We also discuss the relation of the present theory with a many-body extension of electron-positron pair production in nonlinear quantum electrodynamics known as the Schwinger mechanism.

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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