We measure the low-temperature resistance of permalloy break junctions as a function of contact size and the magnetic field angle in applied fields large enough to saturate the magnetization. For both nanometer-scale metallic contacts and tunneling devices we observe large changes in resistance with the angle, as large as 25% in the tunneling regime. The pattern of magnetoresistance is sensitiv...

We have studied the problem of coherent and sequential tunneling through a double barrier structure, assisted by light considered to be present All over the structure, i,e emitter, well and collector as in the experimental evidence. By means of a canonical transformation and in the framework of the time dependent perturbation theory, we have calculated the transmission coefficient and the elect...

We investigate tunneling decay in a magnetic field. Because of broken time-reversal symmetry, the standard WKB technique does not apply. The decay rate and the outcoming wave packet are found from the analysis of the set of the particle Hamiltonian trajectories and its singularities in complex space. The results are applied to tunneling from a strongly correlated 2D electron system in a magneti...

Motivated by the possibility of a string landscape, we reexamine tunneling of a scalar field across single/multiple barriers. Recent investigations have suggested modifications to the usual picture of false vacuum decay that lead to efficient and rapid tunneling in the landscape when certain conditions are met. This can be due to stringy effects (e.g. tunneling via the DBI action), or by effect...

At finite temperature we study the quantum tunneling of magnetization for a small ferromagnetic particle with the biaxial symmetry placed in a magnetic field at an arbitrary angle. We present numerical WKB exponent below the crossover temperature in which the quantum tunneling is affected by the thermal activation, and the approximate form of the WKB exponent around the crossover region. The ef...

Articles you may be interested in Observation of gate bias dependent interface coupling in thin silicon-on-insulator metal-oxide-semiconductor field-effect transistors Mobility comparison between front and back channels in ultrathin silicon-on-insulator metal-oxide-semiconductor field-effect transistors by the front-gate split capacitance-voltage method Appl. Trap evaluations of metal/oxide/sil...

The gate dependence of a Coulomb attractive random telegraph signal is observed in a single-walled carbon nanotube field effect transistor for temperatures varying from 0.32 to 24 K. The mechanism of the Coulomb attractive random telegraph signal is attributed to the carrier tunneling between the carbon nanotube and the Coulomb attractive defect. The random telegraph signal is also studied unde...

The sensitivity of electron tunneling to the phase of an ionizing light field is shown to manifest itself in detectable features in the spectral and temporal evolution of intense few-cycle light pulses in an ionizing medium. An ultrafast buildup of electron density in the regime of tunneling ionization gives rise to a modulation of a few-cycle field wave form and enhances the short-wavelength p...

Scanning Hall Probe Microscopy (SHPM) is a scanning probe microscopy technique developed to observe and image magnetic fields locally. This method is based on application of the Hall Effect, supplied by a micro hall probe attached to the end of cantilever as a sensor.  SHPM provides direct quantitative information on the magnetic state of a material and can also image magnetic induction under a...

In this paper, the performance of a CNT-JLTFET under different values of torsional strains of 0, 3, and 5 degrees has been investigated. Simulation has been carried out using non-equilibrium Green’s function (NEGF) formalism in the mode-space approach and in the ballistic limit. The simulation results indicate that, under torsional strain, an increase occurs in the energy band-gap, and thus the...