English
Related papers

Related papers: Decoherence effects on the tunneling rate of param…

200 papers

We report the observation of enhanced spin dependent shot noise in magnetic tunnel barriers, suggesting transport through localized states within the barrier. This is supported by the existence of negative magnetoresistance and structure in…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 S. Garzon , Y. Chen , R. A. Webb

We review different attempts to show the decoherence process in double-slit-like experiments both for charged particles (electrons) and neutral particles with permanent dipole moments. Interference is studied when electrons or atomic…

Quantum Physics · Physics 2009-11-11 Fernando C. Lombardo , Paula I. Villar

We theoretically investigate the hyperfine-induced decoherence in a pair of spin-cluster qubits, consisting of two exchange-coupled heterometallic wheels. We identify two distinct regimes in the decoherence of intermolecular entanglement…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 A. Szallas , F. Troiani

This paper investigates the problem of a relativistic Dirac half integer spin free particle tunneling through a rectangular quantum-mechanical barrier. If the energy difference between the barrier and the particle is positive, and the…

General Physics · Physics 2017-07-17 Luca Nanni

We have studied the transport process in the two dimensional electron gas (2DEG) in presence of a magnetic field and a dissipative environment at temperature T. By means of imaginary time series functional integral method we calculate the…

Statistical Mechanics · Physics 2009-11-11 Malay Bandyopadhyay

Magnetization measurements of Mn12 molecular nanomagnets with spin ground states of S = 10 and S = 19/2 showresonance tunneling at avoided energy level crossings. The observed oscillations of the tunnel probability as a function of the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 W. Wernsdorfer , N. E. Chakov , G. Christou

The spin-polarized transport is investigated in a new type of magnetic tunnel junction which consists of two ferromagnetic electrodes separated by a magnetic barrier and a nonmagnetic metallic spacer. Based on the transfer matrix method and…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Ali A. Shokri , Alireza Saffarzadeh

An explicit expression is obtained for the phase-time corresponding to tunneling of a (non-relativistic) particle through two rectangular barriers, both in the case of resonant and in the case of non-resonant tunneling. It is shown that the…

Quantum Physics · Physics 2009-11-10 Vladislav S. Olkhovsky , Erasmo Recami , A. K. Zaichenko

We point out a close physical and formal similarity between the problems of electron tunneling in the effective environment and the weak localization effects in the presence of interactions. In both cases the results are expressed in terms…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 D. S. Golubev , A. D. Zaikin

The motion of a particle in a ring of length L is influenced by a dirty metal environment whose fluctuations are characterized by a short correlation distance $\ell << L$. We analyze the induced decoherence process, and compare the results…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Doron Cohen , Baruch Horovitz

We analyse tunnelling of a single particle, whose initial state is given by a superposition of spatially separated wave packet modes. It is shown that "pile up" of different components the scatterer may change the tunnelling probabilities,…

Quantum Physics · Physics 2015-06-11 D. Sokolovski

We review studies on spin-dependent tunneling phenomena in systems containing ferromagnetic nanoparticles. We discuss preparation methods of assembling nanoparticles as well as the mechanisms and results of spin-dependent transport…

Materials Science · Physics 2007-09-20 Kay Yakushiji , Franck Ernult , Seiji Mitani , Koki Takanashi , Hiroyasu Fujimori

We study the decoherence of two coupled spins that interact with a spin-bath environment. It is shown that the connectivity and the coupling strength between the spins in the environment are of crucial importance for the decoherence of the…

Quantum Physics · Physics 2008-10-22 Shengjun Yuan , Mikhail I. Katsnelson , Hans De Raedt

A curious feature of quantum tunneling known as the MacColl-Hartman effect results in the numerical observation that particles can traverse a barrier with effective superluminal speed. However, because tunneling is never certain, any…

Quantum Physics · Physics 2023-05-22 Randall S. Dumont , Tom Rivlin

The evolution of the quantum wave packet describing an atom trapped in the surface-tip junction of the scanning tunneling microscope is investigated by using the time-dependent Schroedinger equation, and by a quasi-classical Hamiltonian…

Quantum Physics · Physics 2008-02-21 M. Grigorescu

A persistent current qubit has two quantum states with opposite currents flowing in a superconducting loop. Their magnetic field couple to nuclear spins. The qubit state is not only perturbed by the spins but it also gets entangled with the…

Condensed Matter · Physics 2007-05-23 Jacek Dziarmaga

We consider a linear quench from the paramagnetic to ferromagnetic phase in the quantum Ising chain interacting with a static spin environment. Both decoherence from the environment and non-adiabaticity of the evolution near a critical…

Quantum Physics · Physics 2016-09-08 Lukasz Cincio , Jacek Dziarmaga , Jakub Meisner , Marek M. Rams

We study theoretically the possibilities of coupling the quantum mechanical motion of a trapped charged particle (e.g. ion or electron) to quantum degrees of freedom of superconducting devices, nano-mechanical resonators and quartz bulk…

Quantum Physics · Physics 2017-03-01 Shlomi Kotler , Raymond W. Simmonds , Dietrich Leibfried , David J. Wineland

Qualitative differences in the spectrum of a superconductor near magnetic impurity pairs with moments aligned parallel and antiparallel are derived. A proposal is made for a new, nonmagnetic scanning tunneling spectroscopy of magnetic…

Superconductivity · Physics 2009-10-31 Michael E. Flatte , David E. Reynolds

Effect of a complicated many-body environment is analyzed on the electron random scattering by a 2D mesoscopic open ballistic structure. A new mechanism of decoherence is proposed. The temperature of the environment is supposed to be zero…

Mesoscale and Nanoscale Physics · Physics 2015-03-13 Valentin V. Sokolov