Conditions for electronic reconstruction at stoichiometric polar/polar interfaces.
Relying on first principles simulations of ZnO(0 0 0 1)/MgO(1 1 1), MgO(1 1 1)/CaO(1 1 1) and AlN(0 0 0 1)/GaN(0 0 0 1) interfaces and examples taken from the literature, we discuss under which conditions stoichiometric polar/polar interfaces may display an electronic reconstruction. We point out the role of the three contributions to the interfacial polarization discontinuity--structure, valence and electronic terms--of interfacial strains, and of finite size effects. Depending upon their relative values, the interfaces may be polar (compensated by an electron reconstruction), non-polar, or polar uncompensated at low thickness. We stress that, in superlattices or heterostructures made of thin layers, the prediction of the interface polarity character from the bulk properties of the two materials may be questionable.
CNRS, UMR 7588, Institut des Nanosciences de Paris, F-75005 Paris, France. Sorbonne Universités, UPMC Université Paris 06, UMR 7588, INSP, F-75005 Paris, France.
Jacek
J
Goniakowski
Claudine
C
Noguera