Transient current spectroscopy of a quantum dot in the Coulomb blockade regime

Toshimasa Fujisawa, Yasuhiro Tokura, Yoshiro Hirayama
2001 Physical Review B (Condensed Matter)  
Transient current spectroscopy is proposed and demonstrated in order to investigate the energy relaxation inside a quantum dot in the Coulomb blockade regime. We employ a fast pulse signal to excite an AlGaAs/GaAs quantum dot to an excited state, and analyze the non-equilibrium transient current as a function of the pulse length. The amplitude and time-constant of the transient current are sensitive to the ground and excited spin states. We find that the spin relaxation time is longer than, at
more » ... is longer than, at least, a few microsecond.
doi:10.1103/physrevb.63.081304 fatcat:sm5bcpp45fdnfcizjspaedvita