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[7]Quantum Transport Characteristics of Radio Frequency Single-Electron Mesoscopic Devices:
The aim of this thesis is to study the quantum transport characteristics through the quantum dot. This quantum dot is weakly coupled to superconducting reservoirs via asymmetric double tunnel barriers of different heights. An expression for the current was derived in terms of the tunneling probabilities through the left and right barriers. Using the transfer matrix method derives these tunneling probabilities. The tunneling of electrons is affected by applying microwave field. The effects of both Coulomb blockade and magnetic field are taken into consideration. It was found that the periodic oscillation of the current with the magnetic field is controlled by the ratio of the frequency of the applied microwave field to the electron cyclotron frequency. Also, the conductance of the present device is investigated when the quantum dot inserted in one arm of the Aharonov-Bohm ring. Our results show that the oscillating conductance is a direct consequence of the asymmetric coupling of the AC-field across the left and right barriers. According to our results, the proposed model of mesoscopic device can be operated as single-electron transistor together with resonant tunneling device.
