Quantum Transport in Mesoscopic Systems

Quantum master-equation approach to quantum transport through mesoscopic systems

For quantum transport through mesoscopic systems, a quantum master-equation approach is developed in terms of compact expressions for the transport current and the reduced density matrix of the system. The present work is an extension of Gurvitz’s approach for quantum transport and quantum measurement, namely, to finite temperature and arbitrary bias voltage. Our derivation starts from a second...

Quantum transport in mesoscopic systems and the measurement problem

We study noninvasive measurement of stationary currents in mesoscopic systems. It is shown that the measurement process is fully described by the Schrödinger equation without any additional reduction postulate and without the introduction of an observer. Nevertheless the possibility of observing a particular state out of coherent superposition leads to collapse of the wave function, even though...

Quantum transport and dynamics of phonons in mesoscopic systems

Recent advances in nanotechnology have shrunk the size of mesoscopic structures. This allows us to investigate the quantum mechanics of mechanical oscillators. In this thesis we focus on two aspects. In Part I, an individual discrete mode structure of an oscillator and its effect to thermal conductance have been thoroughly examined: Specifically, we investigated the reduction in the thermal con...

Heat transport in mesoscopic systems

Phonon heat transport in mesoscopic systems is investigated using methods analogous to the Landauer description of electrical conductance. A “universal heat conductance” expression that depends on the properties of the conducting pathway only through the mode cutoff frequencies is derived. Corrections due to reflections at the junction between the thermal body and the conducting bridge are foun...

Quantum Transport: Persistent Current in Mesoscopic Loops