Surface induced asymmetry of acceptor wave functions.
Measurements of the local density of states of individual acceptors in III-V semiconductors show that the symmetry of the acceptor states strongly depends on the depth of the atom below a (110) surface. Tight-binding calculations performed for a uniformly strained bulk material demonstrate that strain induced by the surface relaxation is responsible for the observed depth-dependent symmetry breaking of acceptor wave functions. As this effect is strongest for weakly bound acceptors, it explains within a unified approach the commonly observed triangular shapes of shallow acceptors and the crosslike shapes of deeply bound acceptor states in III-V materials.
Celebi
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C
COBRA Inter-University Research Institute, Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, NL-5600 MB Eindhoven, The Netherlands.
Garleff
J K
JK
Silov
A Yu
AY
Yakunin
A M
AM
Koenraad
P M
PM
Van Roy
W
W
Tang
J-M
JM
Flatté
M E
ME