Polarization control of the nonlinear emission of semiconductor microcavities.
The degree of circular polarization ( Weierstrass p ) of the nonlinear emission in semiconductor microcavities is controlled by changing the exciton-cavity detuning. The polariton relaxation towards K approximately 0 cavitylike states is governed by final-state stimulated scattering. The helicity of the emission is selected due to the lifting of the degeneracy of the +/-1 spin levels at K approximately 0. At short times after a pulsed excitation Weierstrass p reaches very large values, either positive or negative, as a result of stimulated scattering to the spin level of lowest energy (+1/-1 spin for positive/negative detuning).
Departamento de Física de Materiales C-IV, Universidad Autónoma de Madrid, Cantoblanco, Spain.
M D
MD
Martín
G
G
Aichmayr
L
L
Viña
R
R
André