MBE-grown LaCrO3/SrTiO3(001) exhibits a staggered band alignment with valence and conduction band offsets of 2.45(6) and 0.8(1) eV, respectively. Core-level XPS peak broadening is consistent with no band bending in the SrTiO3 and a gradient of ~200 meV per unit cell in the LaCrO3. This gradient is adequate to trigger an electronic reconstruction, and the attendant transfer of charge from film to substrate, to alleviate the polarity mismatch. However, the interface is insulating because charge redistribution within the CrO2 layers occurs rather than electronic reconstruction to screen the field.
Revised: August 18, 2014 |
Published: November 7, 2011
Citation
Chambers S.A., L. Qiao, T.C. Droubay, T.C. Kaspar, B.W. Arey, and P.V. Sushko. 2011.Band Alignment, Built-In Potential, and the Absence of Conductivity at the LaCrO3/SrTiO3(001) Heterojunction.Physical Review Letters 107, no. 20:Article No. 206802.PNNL-SA-80654.doi:10.1103/PhysRevLett.107.206802