1307.6520 (J. Laverock et al.)

Resonant soft x-ray emission as a bulk probe of correlated electron
behavior in metallic Sr$_x$Ca$_{1-x}$VO$_3$    [PDF]

J. Laverock, B. Chen, K. E. Smith, R. P. Singh, G. Balakrishnan, M. Gu, J. W. Lu, S. A. Wolf, R. M. Qiao, W. Yang, J. Adell

The evolution of electron correlation in Sr$_{x}$Ca$_{1-x}$VO$_3$ has been studied using a combination of bulk-sensitive resonant soft x-ray emission spectroscopy (RXES), surface-sensitive photoemission spectroscopy (PES), and ab initio band structure calculations. We show that the effect of electron correlation is enhanced at the surface. Strong incoherent Hubbard subbands are found to lie ~ 20% closer in energy to the coherent quasiparticle features in surface-sensitive PES measurements compared with those from bulk-sensitive RXES, and a ~ 10% narrowing of the overall bandwidth at the surface is also observed.

View original: http://arxiv.org/abs/1307.6520