Parts | Days | Selection | Search | Downloads | Help

HL: Halbleiterphysik

HL 26: Symposium: Spectroscopy of Single Quantum Dots

HL 26.1: Fachvortrag

Thursday, March 29, 2001, 10:30–11:00, S2

Few-particle effects and coherent control in optics of single and coupled quantum dots — •Elisa Molinari, Filippo Troiani, and Ulrich Hohenester — INFM and Physics Department, University of Modena and Reggio Emilia, 41100 Modena, Italy

Coulomb correlations among electrons and holes in photoexcited semiconductor quantum dots are strongly enhanced by three-dimensional quantum confinement.

We show that each electron-hole configuration leads to its characteristic signature in non-linear optical spectra, that can be quantitatively predicted for realistic dots by our theoretical approach based on the direct diagonalization of the exact many-body hamiltonian. For double dots, the ground-state energy is found to undergo novel transitions between different quantum states as a function of the interdot coupling, favouring multiple exciton occupation of one of the dots at large interdot distances.

We discuss how multi-exciton states can be tailored and exploited for the implementation of coherent-control techniques and all-optical quantum-information processing in single and coupled dot structures.