Spin splitting in a polarized quasi-two-dimensional exciton gas

Дата и время публикации : 1996-09-13T16:49:28Z

Авторы публикации и институты :
L. Vina (UAM, Madrid, Spain)
L. Munoz (UAM, Madrid, Spain)
E. Perez (UAM, Madrid, Spain)
J. Fernandez-Rossier (UAM, Madrid, Spain)
C. Tejedor (UAM, Madrid, Spain)
K. Ploog (PDI, Berlin, Germany)

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: Revtex, four pages; four figures, postscript file Accepted for publication in Physical Review B (Rapid Commun.)
Первичная категория: cond-mat

Все категории : cond-mat

Краткий обзор статьи: We have observed a large spin splitting between "spin" $+1$ and $-1$ heavy-hole excitons, having unbalanced populations, in undoped GaAs/AlAs quantum wells in the absence of any external magnetic field. Time-resolved photoluminescence spectroscopy, under excitation with circularly polarized light, reveals that, for high excitonic density and short times after the pulsed excitation, the emission from majority excitons lies above that of minority ones. The amount of the splitting, which can be as large as 50% of the binding energy, increases with excitonic density and presents a time evolution closely connected with the degree of polarization of the luminescence. Our results are interpreted on the light of a recently developed model, which shows that, while intra-excitonic exchange interaction is responsible for the spin relaxation processes, exciton-exciton interaction produces a breaking of the spin degeneracy in two-dimensional semiconductors.

Category: Physics