We measure electron tunneling in single-molecule transistors made from C140, a molecule with a mass-spring-mass geometry chosen as a model system to study electron-vibration coupling. We observe vibration-assisted tunneling at an energy corresponding to the stretching mode of C140. Molecular modeling provides explanations for why this mode couples more strongly to electron tunneling than the ot...

We theoretically investigate resonant tunneling through S- and U-shaped nanostructured graphene nanoribbons. A rich structure of resonant tunneling peaks is found emanating from different quasi-bound states in the middle region. The tunneling current can be turned on and off by varying the Fermi energy. Tunability of resonant tunneling is realized by changing the width of the left and/or right ...

An experiment has been completed which demonstrated quantum mechanical tunneling of electrons between two gold electrodes separated in vacuum. The tunneling current between the gold electrodes has been measured, for fixed voltages of 0.1 and 0.01 volts, as the electrode spacing was varied from a distance of approximately 2.0 nm down to a point where the electrodes touched. Current changes of ov...

Gate oxide direct tunneling current is the major component of static power dissipation of a CMOS circuit for low-end technology, where the gate dielectric (SiO2) thickness is very low. This paper presents a novel direct tunneling current reduction method during behavioral synthesis of nanometer CMOS circuits. We provide analytical models to calculate the direct tunneling current and the propaga...

We argue that the scanning tunneling microscope (STM) images of resonant states generated by doping Zn or Ni impurities into Cu-O planes of BSCCO are the result of quantum interference of the impurity signal coming from several distinct paths. The impurity image seen on the surface is greatly affected by interlayer tunneling matrix elements. We find that the optimal tunneling path between the S...

Electron tunneling through self-assembled monolayers (SAMs) of alkanethiols was investigated using nanometer scale devices that allow temperature-dependent current-voltage, I(V, T), measurements. The I(V, T) measurement results show, for the first time, temperature-independent electron transport characteristics, proving direct tunneling as the transport mechanism in alkanethiol SAMs. The measur...

Ab initio density functional theory and ballistic transport theory are applied to the calculation of tunneling current through ultra-thin SiO2 gate dielectrics. The Si/SiO2/Si model interface has been constructed by orienting a crystalline SiO2 (β−cristobalite) slab such that the misfit with Si (001) was minimized and no dangling bonds appear at the interface. The structure was then sandwiched ...

We consider tunneling to the continuum in a multi-dimensional potential. It is demonstrate that this problem can be treated as two separate problems: a) a bound state and b) a non-resonance scattering problem, by a proper splitting of the potential into two components. Finally we obtain the resonance energy and the partial tunneling widths in terms of the bound and the scattering state wave fun...

Over 150 lines in six tunneling subbands of an intermolecular vibration located near 25 cm r have been measured with partial hyperflne resolution and assigned to (NH, )2. The transitions sample all three types of tunneling states (A, G, E) and are consistent with the following assumptions: ( 1) G,, is the appropriate molecular symmetry group; (2) the equilibrium structure contains a plane of sy...

Typical dynamical systems have a mixed phase space, in which regions of chaotic motion coexist with regions of regular motion. While classically they are dynamically separated, quantum mechanically, these regions are connected by the fundamental process of tunneling. In this talk we review how to predict dynamical tunneling rates in systems with a mixed phase space by the fictitious integrable ...