We analyze the problem of directed quantum transport induced by external exponentially correlated telegraphic noise. In addition to quantum nature of the heat bath, nonlinearity of the periodic system potential brings in quantum contribution. We observe that quantization, in general, enhances classical current at low temperature, while the differences become insignificant at higher temperature....

Making use of bipolar transport in single-wall carbon nanotube quantum transistors would permit a single device to operate as both a quantum dot and a ballistic conductor or as two quantum dots with different charging energies. Here we report ultra-clean 10 to 100 nm scale suspended nanotube transistors with a large electron-hole transport asymmetry. The devices consist of naked nanotube channe...

This thesis discusses device physics, modeling and design issues of nanoscale transistors at the quantum level. The principle topics addressed in this report are 1) an implementation of appropriate physics and methodology in device modeling, 2) development of a new TCAD (technology computer aided design) tool for quantum level device simulation, 3) examination and assessment of new features of ...

Recent theoretical studies show that decoherence process can enhance transport efficiency in quantum systems. This effect is known as environment-assisted quantum transport (ENAQT). The role of ENAQT in optimal quantum transport is well investigated; however, it is less known how robust ENAQT is with respect to variations in the system or its environment characteristic. Toward answering this qu...

– Phononless plasmon assisted transport through a long disordered array of finite length quantum wires is investigated analytically. Generically strong electron plasmon interaction in quantum wires results in a qualitative change of the temperature dependence of thermally activated resistance in comparison to phonon assisted transport. At high temperatures, the thermally activated resistance is...

ductor devices. A self consistent Schrodinger – Poisson solver allows calculation of bound state energies and associated carrier wave functions self consistently with electrostatic potential. Schrodinger solvers can be combined with Non-equilibrium Green’s Function (NEGF) Approach in order to model ballistic quantum transport in 2D or cylindrical devices with strong transverse confinement. An a...

Carrier transport in modern nanoelectronic devices involves physical scales which require quantum descriptions. Basic quantum mechanics describes systems determined by Hamiltonian state vectors |Ψ>, which provide the spatial and time dependences of the physical observables. A pure state density operator |Ψ><Ψ| as obtained by a single state vector contains the most complete information about the...

Future MOS transistors may operate near their ballistic limits [1], so it is important to understand ballistic device physics and the prospects for achieving quasi-ballistic operation. In this paper, we explore the device design and physics issues of MOSFETs at the scaling limits using semiclassical and full quantum simulations. The device we presume is a double-gate (DG) MOSFET with symmetrica...

Venugopal, Ramesh. Ph.D., Purdue University, August, 2003. Modeling Quantum Transport in Nanoscale Transistors. Major Professor: Mark Lundstrom. As critical transistor dimensions scale below the 100 nm (nanoscale) regime, quantum mechanical effects begin to manifest themselves and affect important device performance metrics. Therefore, simulation tools which can be applied to design nanoscale t...