Spin-polarized tunneling spectroscopy in tunnel junctions with   half-metallic electrodes
  We have studied the magnetoresistance (TMR) of tunnel junctions with electrodes of La2/3Sr1/3MnO3 and we show how the variation of the conductance and TMR with the bias voltage can be exploited to obtain a precise information on the spin and energy dependence of the density of states. Our analysis leads to a quantitative description of the band structure of La2/3Sr1/3MnO3 and allows the determination of the gap delta between the Fermi level and the bottom of the t2g minority spin band, in good agreement with data from spin-polarized inverse photoemission experiments. This shows the potential of magnetic tunnel junctions with half-metallic electrodes for spin-resolved spectroscopic studies. 
M. Bowen, A. Barth\'el\'emy, M. Bibes, E. Jacquet, J.-P. Contour, A.   Fert, F. Ciccacci, L. D\`uo and R. Bertacco