Origin of insulating behavior of the p-type LaAlO3/SrTiO3 interface: Polarization-induced asymmetric distribution of oxygen vacancies

It is revealed from first-principles calculations that polarization-induced asymmetric distribution of oxygen vacancies plays an important role in the insulating behavior at p-type LaAlO3/SrTiO3 interface. The formation energy of the oxygen vacancy (V-O) is much smaller than that at the surface of the LaAlO3 overlayer, causing all the carriers to be compensated by the spontaneously formed V-O's at the interface. In contrast, at an n-type interface, the formation energy of V-O is much higher than that at the surface, and the V-O's formed at the surface enhance the carrier density at the interface. This explains the puzzling behavior of why the p-type interface is always insulating but the n-type interface can be conducting.

Submitted by 阎军 (yanj@red.semi.ac.cn) on 2010-10-11T03:09:40Z No. of bitstreams: 1 Origin of insulating behavior of the p-type LaAlO3-SrTiO3 interface.pdf: 341724 bytes, checksum: 20fb88367043c95ac4d683916691e8b1 (MD5)

Approved for entry into archive by 阎军(yanj@red.semi.ac.cn) on 2010-10-11T03:10:54Z (GMT) No. of bitstreams: 1 Origin of insulating behavior of the p-type LaAlO3-SrTiO3 interface.pdf: 341724 bytes, checksum: 20fb88367043c95ac4d683916691e8b1 (MD5)

Made available in DSpace on 2010-10-11T03:10:54Z (GMT). No. of bitstreams: 1 Origin of insulating behavior of the p-type LaAlO3-SrTiO3 interface.pdf: 341724 bytes, checksum: 20fb88367043c95ac4d683916691e8b1 (MD5) Previous issue date: 2010

The work is supported by the start-up grant to Lixin Zhang from Nankai University in P. R. China. The work at NREL is supported by the U.S. DOE under Contract No. DE-AC36-08GO28308

国际

The work is supported by the start-up grant to Lixin Zhang from Nankai University in P. R. China. The work at NREL is supported by the U.S. DOE under Contract No. DE-AC36-08GO28308