A Study Of Electrons Tunneling And The Transport Of 2DEG

Quantum tunneling, which describes the movement of microcosmicparticles in the frame of quantum mechanics, is a fundamental problem inquantum mechanics.At first, we have studied the fundamental approach to dealing withquantum tunneling potential barrier problem for the microcosmicparticles. For a few cases, its potential is simple and its quantumtunneling probability can be strictly resolved. But as for a majority ofcases, the practical potential is ruleless and indeed arbitrary. Thus, itsquantum tunneling probability can not be strictly resolved. So wedemonstrate the computational method to solve quantum tunnelingproblems which could provide results for analyzing tunneling throughbarriers with arbitrary configurations, and we hold a good result. We havealso compared the results of computation with the exactly solved cases.And then we have found that the transfer matrix method is anapproximate computational method with high precision, which isconsistent with the exactly solved one. From what we have mentionedabove, we have had a general understanding of the quantum tunnelingpotential barrier problem.Next, we have used the transfer matrix method to study the transportproperties of 2DEG (two-dimensional electron gas) passing throughmicroscopic nanostructures. Since microscopic nanostructures hasdemonstrated prospect of application potential, it has received widespreadattention and study in recent years.We have built dissymmetric double-barrier magnetic nanostructures. We have built dissymmetric double-barrier magnetic nanostructures.We took the interaction between electron spin and the magnetic field inthe nanostructure into consideration when we were studying theproperties of transporting electrons passing through nanostructures in2DEG (two-dimensional electron gas), which results in electron spinpolarization effect of electron tunneling potential barrier. Our results haveshown that the magnetic nanostructures have stronger electron spinpolarization effect when the interaction between electron spin anddissymmetrical magnetic field is considered. Meanwhile, we have studiedtheoretically the transport properties of electrons in dissymmetricdouble-barrier magnetic nanostructures, and calculated the transmissionprobability and conductance of the electrons as well. Compared with thesymmetry double magnetic-barriers, the dissymmetry doublemagnetic-barriers have stronger wave-vector-filtering features, but boththe transmission probability and conductance are drastically reduced forelectrons tunneling through dissymmetric double-barrier magneticnanostructures. All these we have discussed will offer a good basis andguidance for furture study.