Fujioka J, Miyasaka S, Tokura Y
Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan.
Phys Rev Lett. 2006 Nov 10;97(19):196401. doi: 10.1103/PhysRevLett.97.196401.
The variation of anisotropic charge dynamics in the course of a filling-control insulator-metal transition (IMT) in La(1-x)Sr(x)VO3 has been investigated by measurements of optical conductivity spectra with the focus on the role of the t(2g)-orbital degree of freedom. The orbitally induced anisotropic feature of the Mott-gap excitation as well as of the doping-induced midinfrared excitation is suppressed with increasing x, and instead the isotropic and incoherent dynamics of the doped hole dominates over the low-energy excitation near and above the IMT point.
通过测量光导率光谱，研究了La(1-x)Sr(x)VO3中填充控制绝缘体-金属转变（IMT）过程中各向异性电荷动力学的变化，重点关注t(2g)轨道自由度的作用。随着x的增加，莫特能隙激发以及掺杂诱导的中红外激发的轨道诱导各向异性特征受到抑制，取而代之的是，掺杂空穴的各向同性和非相干动力学在IMT点附近及以上的低能激发中占主导地位。
