Strain-free polarization superlattice in silicon carbide: a theoretical investigation.
A strain-free superlattice of inversion domains along the hexagonal axis of SiC is investigated by theoretical calculations. The induced polarization causes a zigzag shape in the band edges, leading to spatial separation of photoexcited carriers and to an effective band gap narrowing tunable over a wide range by the geometry and on a smaller scale by the intensity of the excitation. Calculations on the SiC surface indicate that preparation of such a superlattice might be possible in atomic layer epitaxy with properly chosen sources and temperatures.
Deák
Peter
P
Theoretical Physics, University of Paderborn, Warburger Strasse 100, Paderborn D-33098, Germany.
Buruzs
Adam
A
Gali
Adam
A
Frauenheim
Thomas
T