Profiling the interface electron gas of LaAlO3/SrTiO3 heterostructures with hard x-ray photoelectron spectroscopy.

  title={Profiling the interface electron gas of LaAlO3/SrTiO3 heterostructures with hard x-ray photoelectron spectroscopy.},
  author={Michael Sing and G. Berner and Karin Goss and Astrid M. M{\"u}ller and Andreas Ruff and Andreas Wetscherek and S. Thiel and Jochen Mannhart and Stephan Pauli and Christof W. Schneider and Philip R. Willmott and Mihaela Gorgoi and Franz Sch{\"a}fers and Ralph Claessen},
  journal={Physical review letters},
  volume={102 17},
The conducting interface of LaAlO3/SrTiO3 heterostructures has been studied by hard x-ray photoelectron spectroscopy. From the Ti 2p signal and its angle dependence we derive that the thickness of the electron gas is much smaller than the probing depth of 4 nm and that the carrier densities vary with increasing number of LaAlO3 overlayers. Our results point to an electronic reconstruction in the LaAlO3 overlayer as the driving mechanism for the conducting interface and corroborate the recent… 

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