We show that the macroscopic quantum tunnelling of a fluxon in a Josephson junction cannot be described, even qualitatively, as the tunnelling of a quantum particle in a potential U(φ), where the phase difference φ plays the role of particle position, if the length of the junction d exceeds a fluxon length. We calculate the probability per unit time of tunnelling (or escape rate), Γ, which has ...

As MOSFETs are scaled into sub 100 nm (decanano) dimensions, quantum mechanical confinement and tunnelling start to dramatically affect their characteristics. In this paper we describe the introduction of quantum corrections within a 3D drift diffusion simulation framework using quantum potentials. We compare the density gradient (DG) and the effective potential (EP) approaches in term of accur...

In the strong field molecular tunnelling ionization theory (Tong X M 2002 Phys. Rev. A 66 033402), the ionization rate depends on structure parameters of molecules which can be extracted from molecular wavefunctions in the asymptotic region. By using molecular orbitals obtained from standard quantum chemistry packages, we extract these parameters for several selected nonlinear polyatomic molecu...

We discuss the propagation of wave packets through interacting environments. Such environments generally modify the dispersion relation or shape of the wave function. To study such effects in detail, we define the distribution function PX(T ), which describes the arrival time T of a packet at a detector located at point X. We calculate PX(T ) for wave packets travelling through a tunnelling bar...

Transport through a tunnel junction connecting a superconductor to a spin-aligned quantum Hall fluid at filling ν is studied theoretically. The dominant transport channel at low temperatures is the tunnelling of Cooper pairs into edge states of the quantum Hall fluid. This process, which is greatly suppressed at low energies due to both Coulomb and Pauli exclusion effects, leads to a tunnelling...

The scanning tunnelling microscope, initially invented to image surfaces down to the atomic scale, has been further developed in the last few years to an operative tool, with which atoms and molecules can be manipulated at will at low substrate temperatures in different manners to create and investigate artificial structures, whose properties can be investigated employing spectroscopic dI/dV me...