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 1905.08166cond-mat.str-el
收藏

莫特绝缘体中泵浦驱动非热激发的时间和动量分辨隧穿谱

Time and momentum-resolved tunneling spectroscopy of pump-driven non-thermal excitations in Mott insulators

Krissia Zawadzki, Adrian E. Feiguin

摘要:

我们提出了一个计算技术,计算时间和动量分辨的非平衡谱密度的相关系统使用隧道方法类似于扫描隧道光谱。重要的区别是,我们的探针是扩展的,基本上是样品的副本,允许提取激发的动量信息。我们通过测量Mott绝缘扩展Hubbard链在突然猝灭后的光谱来说明该方法,并借助含时密度矩阵重整化群(tDMRG)计算。我们表明,该系统实现了一个非热状态,这是一个混合物的自旋和电荷密度波状态,与相应的签名是可识别的间隙子带。特别是,我们确定了一个带的激子和一个稳定的反束缚态在高能量,获得增强的可见性后,泵。我们不欣赏明显的弛豫时间尺度内考虑,这是由于缺乏衰变通道,由于自旋-电荷分离。这些思想可以很容易地应用于研究相关驱动的非平衡过程的瞬态动力学和谱特征。

英文摘要:

We present a computational technique to calculate time and momentum resolved non-equilibrium spectral density of correlated systems using a tunneling approach akin scanning tunneling spectroscopy. The important difference is that our probe is extended, basically a copy of the sample, allowing one to extract the momentum information of the excitations. We illustrate the method by measuring the spectrum of a Mott-insulating extended Hubbard chain after a sudden quench with the aid of time-dependent density matrix renormalization group (tDMRG) calculations. We demonstrate that the system realizes a non-thermal state that is an admixture of spin and charge density wave states, with corresponding signatures that are recognizable as in-gap sub-bands. In particular, we identify a band of excitons and one of stable anti-bound states at high energies that gains enhanced visibility after the pump. We do not appreciate noticeable relaxation within the time-scales considered, which is attributed to the lack of decay channels due to spin-charge separation. These ideas can be readily applied to study transient dynamics and spectral signatures of correlation-driven non-equilibrium processes.

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。

↑