Abstract
We have studied the unoccupied electronic structure of the band insulator , the Mott insulator , and with a metal-insulator transition (MIT) around by means of resonant inverse photoemission spectroscopy (RIPES). The partial density of states of deduced from the on- and off-resonance RIPES spectra is in good agreement with results of a band-structure calculation, while that of is explained based on a calculation with the dynamical mean-field theory taking into account an electron correlation. In the case of , we have successfully observed the temperature dependence of RIPES spectra across MIT; the intensity of the incoherent part (a remnant of the upper Hubbard bands) relative to the coherent part (quasiparticle bands) is reduced with decreasing temperature from the insulator to metal phases.
1 More- Received 16 December 2006
DOI:https://doi.org/10.1103/PhysRevB.75.205124
©2007 American Physical Society