Studies on Tunneling Characteristics on Asymmetric GaAs/AlAs Double-Barrier Structures

The peculiar differences in tunneling characteristics measured from a number of asymmetric GaAs/ AlAs double-barrier resonant-tunneling structures under two opposite biases have systematically been studied. It is found that LO phonon-assisted tunneling in two opposite directions may possibly be controlled by the different dwell times of traversing electrons in the well as the structure is positively or negatively biased.