DYNAMICS OF ELECTRON-CAPTURE INTO QUANTUM WIRES

We report direct measurements of carrier trapping from three-dimension al states into spatially confined one-dimensional states in GaAs quant um wires. In spite of the small wire volume, very fast trapping (less than or equal to 10 ps) is observed in V-groove wires. Theoretical cal culations of trapping via optical-phonon emission, based on an accurat e band-structure determination, shows that this arises because of stro ng overlap of initial extended and final confined electron states.