论文标题
fete $ _ {1-x} $ se $ _x $中的轨道选择莫特阶段的非热出现
Non-Thermal Emergence of an Orbital-Selective Mott Phase in FeTe$_{1-x}$Se$_x$
论文作者
论文摘要
电子相关对于高温超导性至关重要。基于铁的超导体被认为具有中等的相关强度，结合其多轨本质，使它们成为出现外来现象的引人入胜的平台。一种特别惊人的形式是轨道选择性莫特相的出现，其中轨道子集的定位导致急剧重建的费米表面。在这里，我们报告了Fermi表面从FESE重组的光谱证据，因为SE被TE取代。我们发现了一种特别透明的方法，可以通过抑制$ d_ {xy} $电子轨道的定位，并与更连贯的$ d $电子轨道抑制其杂交，从而导致轨道依赖性光谱重量接近Fermi水平的重新分配。费米表面的这些值得注意的特征伴随着$ d_ {xy} $ orbital中频段恢复的不同行为。我们的理论计算进一步支持了我们所有的观察结果，它们是从强度相关的金属阶段转变为fete $ _ {1-x} $ _x $ _x $ se浓度的轨道选择性莫特相的显着光谱特征。
Electronic correlation is of fundamental importance to high temperature superconductivity. Iron-based superconductors are believed to possess moderate correlation strength, which combined with their multi-orbital nature makes them a fascinating platform for the emergence of exotic phenomena. A particularly striking form is the emergence of an orbital selective Mott phase, where the localization of a subset of orbitals leads to a drastically reconstructed Fermi surface. Here, we report spectroscopic evidence of the reorganization of the Fermi surface from FeSe to FeTe as Se is substituted by Te. We uncover a particularly transparent way to visualize the localization of the $d_{xy}$ electron orbital through the suppression of its hybridization with the more coherent $d$ electron orbitals, which leads to a redistribution of the orbital-dependent spectral weight near the Fermi level. These noteworthy features of the Fermi surface are accompanied by a divergent behavior of a band renormalization in the $d_{xy}$ orbital. All of our observations are further supported by our theoretical calculations to be salient spectroscopic signatures of such a non-thermal evolution from a strongly correlated metallic phase towards an orbital-selective Mott phase in FeTe$_{1-x}$Se$_x$ as Se concentration is reduced.
