Lifetime of resonant state in a spherical quantum dot

This paper calculates the lifetime of resonant state andtransmission probability of a single electron tunnelling in aspherical quantum dot (SQD) structure by using the transfer matrixtechnique. In the SQD, the electron is confined both transversallyand longitudinally, the motion in the transverse and longitudinaldirections is separated by using the adiabatic approximation theory.Meanwhile, the energy levels of the former are considered as theeffective confining potential. The numerical calculations are carried outfor the SQD consisting of GaAs/InAs material. The obtained results show that thebigger radius of the quantum dot not only leads significantly to the shiftsof resonant peaks toward the low-energy region, but also causes thelengthening of the lifetime of resonant state. The lifetime of resonantstate can be calculated from the uncertainty principle between the energyhalf width and lifetime.