Time-dependent Transport in Wide-Narrow-Wide Quantum Devices

• Main Authors: Chen, Li-Wei, 陳力瑋
• Other Authors: Cheng, Shun-Jen
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/42476883951493685448

碩士 === 國立交通大學 === 電子物理系所 === 100 === We consider a semiconductor quantum device that is transversely confined by a pair of split-gate forming a quasi-one-dimensional narrow channel and is biased by the source and drain electrodes. Both the finite-bias and the finite-temperature effects are explicitly included in our calculation. In order to investigate the time-dependent transport behavior, we consider a top-gate in front of the split-gate for generating time-periodic potential. The nonadiabatic mode-mixing features between the narrow channel and the leads are included in the calculation. In this work, we have analyzed the quantum transport properties involving the inter-subband transitions due to the mode-mixing effects and the inter-sideband transitions due to the time-periodic potential. Both the photon-assisted and the photon-suppressed features can be found in conductance as a funtion of the incident electron energy. Moreover, we explicitly include the finite-bias and finite-temperaure effects to investigate the nonlinear quantum transport and thermal broadening properties.