Excitons, biexcitons, and dephasing in GaAs T-shaped quantum wires measured by four-wave mixing

Summary form only given. The realization of one-dimensional (1D) semiconductor nanostructures with large confinement energies is of importance for device applications. Different techniques such as growth on tilted substrates (Serpentine superlattices) or prepatterned substrates (V-groove quantum wins), and the cleaved-edge overgrowth of T-shaped structures have been demonstrated. For the T-shaped structures, the confinement energy has been recently increased to above 2 k/sub B/T at room temperature by optimizing structure parameters. Here we investigate the excitonic properties of a high quality T-shaped wire sample by four-wave mixing. It is a confinement optimised structure with 20 meV exciton confinement energy and only 3 meV in homogeneous width of the exciton resonance.