The Transportation Properties In Periodic Coupled Quantum Dots

Based on S.A.Gurvitz's research about quantum dot system, this thesis discusses the transportation and the measurement in periodic coupled quantum dots. Due to tunneling effect of quantum dot, electron'flow generates electricity in the system under the large bias and zero temperature. Using the method of solving Shrodinger equation and numerical calculation, we obtains the relation between the electricity and the driving frequency. The results show that the graph of electricity and frequency has a shape of parabola, and the electricity reaches its maximum when frequency's value is equal to energy difference of quantum dots. Therefore, the system's electricity can be controlled through driving frequency. However ,we don't know whether a electron is in the quantum dot or not. Then, we use the instrument—quantum point contract(QPC), which consists of two electron reservoirs and also has the electricity in it. QPC is sensitive to electron around it, and the QPC's electricity changes owing to Coulomb electron-electron interaction, so measuring QPC's electricity indicates quantum dot's occupation. At last, we also analysis the impact of QPC and periodic field on the electricity of the periodic coupled quantum dots.