材料的光学驱动已成为控制其性质的多功能工具,其中光致超导性是最引人入胜的例子之一。在这项工作中,我们证明了与电子带间跃迁耦合的光或晶格振动会自然产生电子-电子吸引力,当底层玻色子被驱动到非热态时,这种吸引力可能会增强。我们发现,当将玻色子频率调谐至接近两个电子能带之间的能量差时,该现象会被共振放大。这一结果为光致超导性提供了简单的微观机制,并为设计可实现光致超导性的新平台提供了方案。我们提出了一个由graphene-hBN-SrTiO$_3$异质结构组成的具体装置,并估算了在驱动系统时可能实现的超导转变温度$T_{\ m c}$。
英文摘要:
Optical driving of materials has emerged as a versatile tool to control their properties, with photo-induced superconductivity being among the most fascinating examples. In this work, we show that light or lattice vibrations coupled to an electronic interband transition naturally give rise to electron-electron attraction that may be enhanced when the underlying boson is driven into a non-thermal state. We find this phenomenon to be resonantly amplified when tuning the boson's frequency close to the energy difference between the two electronic bands. This result offers a simple microscopic mechanism for photo-induced superconductivity and provides a recipe for designing new platforms in which light-induced superconductivity can be realized. We propose a concrete setup consisting of a graphene-hBN-SrTiO$_3$ heterostructure, for which we estimate a superconducting $T_{\rm c}$ that may be achieved upon driving the system.
Photoinduced Suppression of Superconductivity in Bi$_2$Sr$_2$Ca$_2$Cu$_3$O$_{10+δ}$
高温超导体中的超导性是通过将电荷载流子引入到含有CuO $_2$平面的铜氧化物绝缘体中来实现的。这些CuO $_2$平面的扰动通过强烈影响电子环境来抑制超导性。本文利用Cu离子在CuO $_2$平面上的光致电子改性研究了Bi $_2$ Sr $_2$ Ca $_2$ Cu $_3$ O $_{10+δ}$中局域微扰的影响。这种方法已用于抑制超导转变温度T $_c$。我们表明,我们的结果光致抑制的超导性是一致的情况下,基于钉扎的波动条纹在Bi $_2$ Sr $_2$ Ca $_2$ Cu $_3$ O $_{10+δ}$。
Evidence for metastable photo-induced superconductivity in K$_3$C$_{60}$
远红外和中红外光脉冲在复杂材料中诱导非平衡非常规有序,包括量子顺电体中的光致铁电性,反铁磁体中的磁极化以及铜氧化物和有机导体正常态中的瞬态超导关联。在非平衡超导的情况下,飞秒驱动通常会导致激发后立即消失的电子特性,证明缺乏内在刚性的状态。在这里,我们利用一种新的光学设备来驱动金属K $_3$ C $_{60}$与中红外脉冲的可调持续时间,范围在1皮秒和1纳秒之间。在飞秒激发的短时间窗口内观察到的类似超导的光学性质在这里被证明在持续的光学驱动下变得亚稳态,寿命超过10纳秒。在这些时间尺度上,直接的电探测成为可能,产生一个非常小的电阻。这种巨大的正光电导对于金属来说是非常不寻常的,当与瞬态光电导一起考虑时,它相当暗示亚稳态光致超导性。
Angle-Resolved Photoemission Spectroscopy of Iron-Chalcogenide Superconductor Fe1.03Te0.7Se0.3 : Strong-Coupling Superconductivity and Universality of Inter-Band Scattering
Signatures of three-dimensional photo-induced superconductivity in YBa$_2$Cu$_3$O$_{6.48}$
Max Planck Institute for the Structure and Dynamics of Matter(马普物质结构与动力学研究所);Physics Department, Politecnico di Milano(米兰理工大学物理系);Max Planck Institute for Solid State Research(马普固态研究所);Department of Physics, Clarendon Laboratory, University of Oxford(牛津大学克拉伦登实验室物理系)
Giant Resonant Enhancement of Photoinduced Dynamical Cooper Pairing, far above $T_c$
Harvard University(哈佛大学);ETH Zürich(苏黎世联邦理工学院);Max Planck Institute for the Physics of Complex Systems(马克斯·普朗克复杂系统物理研究所);Max Planck Institute for the Structure and Dynamics of Matter(马克斯·普朗克物质结构动力学研究所);University of Oxford(牛津大学)