Antibonding ground states in InAs quantum-dot molecules.
Coherent tunneling between two InAs quantum dots forms delocalized molecular states. Using magnetophotoluminescence spectroscopy we show that when holes tunnel through a thin barrier, the lowest energy molecular state has bonding orbital character. However, as the thickness of the barrier increases, the molecular ground state changes character from a bonding orbital to an antibonding orbital, confirming recent theoretical predictions. We explain how the spin-orbit interaction causes this counterintuitive reversal by using a four-band k.p model and atomistic calculations that account for strain.
Doty
M F
MF
Naval Research Laboratory, Washington, DC 20375, USA. doty@udel.edu
Climente
J I
JI
Korkusinski
M
M
Scheibner
M
M
Bracker
A S
AS
Hawrylak
P
P
Gammon
D
D