Uniform And Non-uniform Distribution Of State Features Of The System Can Trap More Potential

Since the advent of nanostructure devices, the quantum well systems have been attracted widespread attention. Due to they have some newfangled physical effects with ultralow dimension characteristic, including Quantum tunnel effects, Quantum size effects, Energy level splittings, continuous resonant tunneling phenomena, etc. which can improve the availability of electronic equipments and photonic devices. One of these problems studied is that solving the Schrodinger equation and deducing by using different methods, then calculating the transmissivity, reflectivity, bound levels, etc. In recent years, a large number of scholars have been carriying on the research for different shapes of quantum wells with diverse methods.In this paper, Based on the standard transfer matrix method, the coupling mechanism between wave vectors of different regions in double potential well has been investigated, the physical mechanism of energy states splittings have been explained and the energy state characteristics of the uniform and non-uniform distribution of multi-potential well systems (MWQ) have been theoretically studied.It is important scientific significance for understanding energy state distribute of semiconductor multiple quantum wells structure and for preparation of quantum devices with practical significanceThis paper is mainly divided into four Sections:In section I. The basic theory of one-dimensional quantum wellWe focuse on the penetration problems about the one-dimensional quantum well system. Through theoretical analysis and discussion, we describe theories of the transmissivity, reflectivity, and the bound levels of the particles in one dimensional square barrier, the square potential well and δ potential wells known.In section Ⅱ. The transfer matrix method of the tunneling effects in one-dimensional N-potential wellsThe derivations of penetration formula of the particles are carried in a single, two, and three of one dimensional equivalent width spacing square potential barriers by solving the Schrodinger equations and using the transfer matrix methods. And we summarized the analytical expression of the particles tunneling one-dimensional N square potential barriers. In theory we describe in details how to deal with N-matrix multiplication. Therefore, these methods more easily can be calculated the transmissivity and reflectivity of particles tunneling square potential barriers with an arbitrary number and we conduct a simple numerical simulation. It is convenient and feasible to study resonant tunneling phenomena in a multi-barrier using this result.In section III Research on the energy level splittings of double potential wellsDouble-potential-well is a basic structure in the semiconductor resonant tunneling devices. The movement of electrons in a potential well can be obtained by solving the Schrodinger equation or using the transfer matrix method, and which can be described the transmission of the wave function in the system. Using the transfer matrix method study the electronic coupling between the double potential well and multiple potential well in different regions of the wave function. Analysis and interpretation of the physical mechanism of energy state split in a multi quantum well system by more straightforward image form a new perspective are carried and we explain the width of the barrier effect on energy states split from the level of quantum physics. These results have important scientific significance and application values for understanding the double potential well and a complex combination of multi-well devices.In section IV Research on the tunneling properties of Mutiple quantum well structureTunneling in finite superlattices, high field domain formation in superlattices, and sequential resonant tunneling phenomena in multi-quantum well (MQ W) superlattices have already been investigated. Most of the previous studies were based on the sysmetric and uniform MQW structures. In some case, it has been seen that asymmetry may improve the performance of MQW based devices. Using the transfer matrix method studied some of the characteristics of the non-uniform and asymmetric multiple quantum well structure. Mainly consist of transmission spectrum characteristics of highly uniform distribution of the multi-barrier system、transmission spectrum characteristics of highly non-uniform distribution of the multi-barrier system、the effect on the transmittance of barrier and potential well width ratio.