Pure circular polarization electroluminescence at room temperature with spin-polarized light-emitting diodes.
Proc Natl Acad Sci U S A
; 114(8): 1783-1788, 2017 02 21.
Article
em En
| MEDLINE
| ID: mdl-28174272
ABSTRACT
We report the room-temperature electroluminescence (EL) with nearly pure circular polarization (CP) from GaAs-based spin-polarized light-emitting diodes (spin-LEDs). External magnetic fields are not used during device operation. There are two small schemes in the tested spin-LEDs first, the stripe-laser-like structure that helps intensify the EL light at the cleaved side walls below the spin injector Fe slab, and second, the crystalline AlO x spin-tunnel barrier that ensures electrically stable device operation. The purity of CP is depressively low in the low current density (J) region, whereas it increases steeply and reaches close to the pure CP when J > 100 A/cm2 There, either right- or left-handed CP component is significantly suppressed depending on the direction of magnetization of the spin injector. Spin-dependent reabsorption, spin-induced birefringence, and optical spin-axis conversion are suggested to account for the observed experimental results.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Proc Natl Acad Sci U S A
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Japão