We have measured the tunnelling between 2 two-dimensional electron gases at magnetic fields B up to 25 T. When the carrier densities of the two electron layers are matched and for filling factors v < 1, we observe a clear gap in the differential conductance dI/d V as a function of the voltage Vsd applied between the layers. We have measured tunnelling peak positions and fitted gap parameters d ...

Energetic acetone cations decay by methane or methyl radical loss. Although the methane-loss barrier to form the ketene cation is higher and the activation entropy is lower, it has a significant branching ratio at low energies thanks to quantum tunnelling. H-atom tunnelling can be selectively quenched and the methane-loss channel suppressed quantitatively by deuteration.

An unusual dinuclear Yb(2) complex isolated using a mixed ligand strategy leads to field-induced SMM behaviour. Low magnetic axiality and a large tunnelling gap lead to significant quantum tunnelling of the magnetisation, which was reduced under an applied static optimum field of 1600 Oe.

We present phonon spectra of very thin evaporated amorphous films of SiOx, obtained by inelastic electron tunnelling spectroscopy. The broad features of the results are similar to those found in neutron-scattering, Raman and infra-red measurements on bulk vitreous SiO2 but there are differences of detail. The results show inelastic tunnelling spectroscopy to be a powerful technique for the stud...

BACKGROUND The tunnelling as opposed to the open harvest technique for harvesting long saphenous vein for coronary artery bypass procedures is a less frequently used technique as it requires more handling of the vein and this may induce trauma. This study aims to compare the degree of endothelial denudation and donor site morbidity between the two different harvest techniques. METHODS Sapheno...

greater levels of complexity in tunnelling with tunnel boring machine (tbm) allow higher chances of failures that may increase the potential hazardous risks. this paper presents the results of a study on tbm reliability using risk analysis. machinery failure mode and effect analysis was applied to analyze the risks of a tbm using qs9000 and sae.j1739 recommendations. for this purpose, 48 failur...

Recent studies of advanced materials have succeeded in obtaining a whole new class of composites such as nanometre sized particles [1] and structures [2] with significant potential for field emission (FE) applications. While bulk emissive materials, such as metals and in most cases semiconductors exhibit smooth upward current-voltage (I-V) characteristics, FE from nanostructured materials often...

As MOSFETs are scaled into the deep sub-micron (decanano) regime, quantum mechanical confinement and tunnelling start to dramatically affect their characteristics. It has already been demonstrated that the density gradient approach can be successfully calibrated in respect of vertical quantum confinement at the Si/SiO2 interface and can reproduce accurately the quantum mechanical threshold volt...

We show that the single-particle polaron Green's function describes SIS tunnelling in cuprates, including the absence of Ohm's law at high voltages, the dip/hump features in the first derivative of the current, a substantial incoherent spectral weight beyond quasiparticle peaks and unusual shape of the peaks. The theory allows us to determine the characteristic phonon frequencies , normal and s...