Related papers: Current and noise in a model of an AC-STM molecule…
We report measurements of photon-assisted transport and noise in a tunnel junction in the regime of dynamical Coulomb blockade. We have measured both dc non-linear transport and low frequency noise in the presence of an ac excitation at…
Photo-assisted transport through a mesoscopic conductor occurs when an oscillatory (AC) voltage is superposed to the constant (DC) bias which is imposed on this conductor. Of particular interest is the photo assisted shot noise, which has…
We consider electrical transport through single molecules coupled to metal electrodes via tunneling barriers. Approximating the molecule by the Anderson impurity model as the simplest model which includes Coulomb charging effects, we extend…
We determine the zero-frequency charge current noise in a metal-molecule-metal junction embedded in a thermal environment, e.g., a solvent, dominated by sequential charge transmission described by a classical master equation, and study its…
In scanning tunneling microscopy induced luminescence (STML), the photon counting is measured to reflect the single-molecule properties, e.g., the first molecular excited state. The energy of the first excited state is typically determined…
This thesis investigates the mechanically controlled break junctions, with a particular emphasis on elucidating the behaviour of molecular currents at room temperature. The core of this experimental investigation involves a detailed…
We investigate photo assisted electronic transport in a normal-metal/BCS-superconductor junction with a microscopic Hamiltonian approach, for several types of periodic voltage drives applied on the normal-metal side. The time-dependent…
We study inelastic effects on the electronic current noise in molecular junctions, due to the coupling between transport electrons and vibrational degrees of freedom. Using a full counting statistics approach based on the generalized…
Atomic-scale junctions are a powerful tool to study quantum transport, and are frequently examined through the mechanically controllable break junction technique (MCBJ). The junction-to-junction variation of atomic configurations often…
The effect of an AC perturbation on the shot noise of a fractional quantum Hall fluid is studied both in the weak and the strong backscattering regimes. It is known that the zero-frequency current is linear in the bias voltage, while the…
We derive the symmetrized current-noise spectrum of a quantum dot, which is weakly tunnel-coupled to an electron reservoir and driven by a slow time-dependent gate voltage. This setup can be operated as an on-demand emitter of single…
Electronic transport in a triple quantum dot shuttle device in the presence of an ac field is analyzed within a fully quantum mechanical framework. A generalized density matrix formalism is used to describe the time evolution for electronic…
We present a fully nonequilibrium calculation of the low temperature transport properties of a quantum dot in the Kondo regime when an AC potential is applied to the gate voltage. We solve a time dependent Anderson model with finite on-site…
Using a scanning tunneling microscope we have measured the quantum conductance through a PTCDA molecule for different configurations of the tip-molecule-surface junction. A peculiar conductance resonance arises at the Fermi level for…
We investigate theoretically and experimentally stochastic resonance in a quantum dot coupled to electron source and drain via time-dependent tunnel barriers. A central finding is a transition visible in the current noise spectrum as a…
Using the Keldysh nonequilibrium Green function technique, we study the current and shot noise spectroscopy of a single molecular quantum dot coupled to a local phonon mode. It is found that in the presence of electron-phonon coupling, in…
Scanning tunneling microscope induced light emission from an atomic or molecular junction has been probed from the tunneling to contact regime in recent experiments. There, the intensity of the light emission shows strong correlation with…
Scanning Tunneling Microscopy (STM) has revolutionized our atomic scale understanding of surfaces and accelerated progress in nanotechnology. This technique, however, is restricted to metal or semiconducting samples, as it requires a tiny…
Electronic properties of heterostructures in which a finite number of Mott-insulator layers are sandwiched by semi-infinite metallic leads are investigated by using the dynamical-mean-field method combined with the Keldysh Green's function…
Electron transport characteristics are investigated through some molecular chains attached to two non-superconducting electrodes by the use of Green's function method. Here we do parametric calculations based on the tight-binding…