Electronic properties have been measured as function of the distance to the interface between La2/3Ca1/3MnO3 and Nb-doped SrTiO3.
Probing a complex oxide interface directly
A novel way to directly detect the electronic properties at a complex oxide interface has been demonstrated by users from Argonne’s Advanced Photon Source working collaboratively with researchers in the Electronic & Magnetic Materials Devices Group. While powerful spatially resolved tools exist for visualizing the chemical and magnetic structure of an interface, direct observation of electronic behavior across the interface presents a major experimental challenge. The scientists harnessed the high sensitivity to electronic local density of states (LDOS) of cross-sectional scanning tunneling microscopy and spectroscopy (XSTM/S) to visualize electronic properties at the interface between colossal magnetoresistant manganite La2/3Ca1/3MnO3 and semiconducting Nb-doped SrTiO3. By extending XSTM/S to the interface, they mapped the LDOS across the boundary, unambiguously visualizing the interface by the location of the valence band, and elucidated the fundamental issue of band alignment at a complex oxide heterointerface.
T.Y. Chien, J. Liu, J. Chakhalian, N. P. Guisinger, and J. W. Freeland, Phys. Rev. B, 82, 041101(R) (2010). Editor’s Suggestion