de' Medici Luca, Hassan S R, Capone Massimo, Dai Xi
Department of Physics and Center for Materials Theory, Rutgers University, Piscataway New Jersey 08854, USA.
Phys Rev Lett. 2009 Mar 27;102(12):126401. doi: 10.1103/PhysRevLett.102.126401. Epub 2009 Mar 23.
We outline a general mechanism for orbital-selective Mott transition, the coexistence of both itinerant and localized conduction electrons, and show how it can take place in a wide range of realistic situations, even for bands of identical width and correlation, provided a crystal field splits the energy levels in manifolds with different degeneracies and the exchange coupling is large enough to reduce orbital fluctuations. The mechanism relies on the different kinetic energy in manifolds with different degeneracy. This phase has Curie-Weiss susceptibility and non-Fermi-liquid behavior, which disappear at a critical doping, all of which is reminiscent of the physics of the pnictides.
我们概述了一种用于轨道选择性莫特转变、巡游和局域传导电子共存的通用机制，并展示了即使对于具有相同带宽和关联的能带，在一系列现实情况下它是如何发生的，前提是晶体场将能级分裂为具有不同简并度的多重态，并且交换耦合足够大以减少轨道涨落。该机制依赖于具有不同简并度的多重态中的不同动能。这个相具有居里 - 外斯磁化率和非费米液体行为，它们在临界掺杂时消失，所有这些都让人联想到铁基超导体的物理性质。
