State Selective Pumping Reveals Spin-Relaxation Pathways in CdSe Quantum Dots
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en
Article de revue
Este ítem está publicado en
Nano Letters. 2014-07-21, vol. 14, n° 8, p. 4480-4485
American Chemical Society
Resumen en inglés
The band-edge exciton in elongated CdSe nanocrystals is composed of an upper and lower manifold associated with heavy and light holes in which the energy separation is sensitive to the nanocrystal shape. Using resonant ...Leer más >
The band-edge exciton in elongated CdSe nanocrystals is composed of an upper and lower manifold associated with heavy and light holes in which the energy separation is sensitive to the nanocrystal shape. Using resonant photoluminescence excitation, we probe the upper heavy hole exciton manifold and find rapid relaxation to the lower light hole manifold on a 5 ps time scale. State selective excitation allows the preparation of single quantum states in this system. We used this to map the hole spin relaxation pathways between the fine structure sublevels, which have energy splittings incommensurate with either optical or acoustic phonon energies. This reveals a hitherto unexpected hole spin-relaxation channel in these materials.< Leer menos
Palabras clave en inglés
CdSe
single nanocrystal
Photoluminescence
Photoluminescence excitation
quantum dot
spin relaxation
Orígen
Importado de HalCentros de investigación