Theoretical Study Of Electron Tunneling Lifetime In One-Dimensional Structures

Quantum tunneling of electron is one of the most amazing phenomena in quantum mechanics field. In 1931 for the first time Condon put forward the question "how long does the particle tunneling barriers need?" Afterwards, MacColl, Wigner, Hartman also conducted studies on this topic. Since 1980s, the development of the semiconductor manufacturing technology has stimulated, great scientific interest in tunneling time again. As is known to us, tunneling time could not be directly calculated by classic quantum methods because of Uncertain Principle Theory, which indicates a limitation on accuracy of simultaneous measurement of observables such as the position and the momentum of a particle. But it might be measured from the point that changes of moving state need time. Therefore research on tunneling time might enhance the knowledge of tunneling process to supply a theory for semiconductors manufacturing.In this work, the tunneling time of an electron in single-barrier, double-barrier and multi-barrier structures was studied using a Projected Green function method (PGF). PGF was applied to quantum structures and the results are helpful for understanding the device structure nature. One-dimensional AlGaAs and AIAs structures are considered in this study, and results are analyzed visually with the aid of Origin software.The tunneling time, the important parameter in evaluating the performance of different electronic devices, is dependent on the barrier structure strongly. So, we analyzed the effect of well width and barrier thickness on the tunneling time, in order to comprehend the tunneling process of high-speed devices better in the future. The study indicates that the limitation of lifetime by the operation speed of resonant tunneling devices can be removed by controlling in thickness of barriers precisely to realize well-defined devices.