COHERENT CONTROL OF EXCITON DENSITY AND SPIN

Citation
Ap. Heberle et al., COHERENT CONTROL OF EXCITON DENSITY AND SPIN, IEEE journal of selected topics in quantum electronics, 2(3), 1996, pp. 769-775
Citations number
18
Categorie Soggetti
Engineering, Eletrical & Electronic",Optics
ISSN journal
1077260X
Volume
2
Issue
3
Year of publication
1996
Pages
769 - 775
Database
ISI
SICI code
1077-260X(1996)2:3<769:CCOEDA>2.0.ZU;2-9
Abstract
We demonstrate femtosecond coherent control of excitons in quantum wel ls with phase-locked pairs of 100 fs infrared pulses. Copolarized pump pulses allow coherent control of exciton density and coherent destruc tion of excitons within a few hundred femtoseconds of their creation. This technique thus promises to avoid speed penalties in devices assoc iated with long-lived persistent carrier populations, Cross-polarized pump pulses allow coherent control of spin dynamics and conversion of unpolarized excitons into spin polarized ones. Carrier density and spi n are determined, respectively, from the differential reflection and f rom the Faraday rotation of a third probe pulse. The experimental resu lts are in good agreement with calculations based on the semiconductor Bloch equations.