Related papers: Lower Bound on Quantum Tunneling for Strong Magnet…
We establish a tunneling formula for a Schr\"odinger operator with symmetric double-well potential and homogeneous magnetic field, in dimension two. Each well is assumed to be radially symmetric and compactly supported. We obtain an…
Quantum tunneling is the quantum-mechanical effect where a particle tunnels through a classically forbidden region. Double Square Well Potential (DSWP) is a system where this phenomenon is feasible. Numerous phenomena can be illustrated by…
We present a new theoretical approach to describe the quantum behavior of a macroscopic system interacting with an external irradiation field, close to the resonant condition. Here we consider the extremely underdamped regime for a system…
A prime example of quantum tunnelling is the semiclassical 'energy splitting' of the levels of a symmetrical double well potential, or equivalently the flipping rate of an instanton. Curiously the accepted expression for the ground state…
We explore a regime of unipolar electronic transport in a multiple quantum well structure with very large current discontinuities - up to five orders of magnitude. Magneto-transport experiments reveal different transport regimes. Quantum…
A tunnel magnetic junction is considered with magnetic hard and magnetic soft layers of cubic symmetry. The magnetic switching is analyzed of the layers by a magnetic field perpendicular to the initial magnetizations. In such a situation,…
We employ a magnetocapacitance technique to study the spectrum of the soft two-subband (or double-layer) electron system in a parabolic quantum well with a narrow tunnel barrier in the centre. In this system unbalanced by gate depletion, at…
A simple approximate solution for the quantum-mechanical quartic oscillator $V= m^2 x^2+g x^4$ in the double-well regime $m^2<0$ at arbitrary $g \geq 0$ is presented. It is based on a combining of perturbation theory near true minima of the…
We report on tunneling experiment between two quantum Hall droplets separated by a nearly ideal tunnel barrier. The device is produced by cleaved edge overgrowth that laterally juxtaposes two two-dimensional electron systems across a high…
A negative magnetoresistance under the in-plane magnetic field, reaching maximum 30-40% of its zero-field value in fields higher than ~12 T, has been found in wide Ge_{1-x}Si_x/Ge/p-Ge_{1-x}Si_x quantum wells (QW) containing the…
The solution to a problem in quantum mechanics is generally a linear superposition of states. The solutions for double well potentials epitomize this property, and go even further than this: they can often be described by an effective model…
The weak-localization contribution \delta\sigma(B) to the conductivity of a tunnel-coupled double-layer electron system is evaluated and its behavior in weak magnetic fields B perpendicular or parallel to the layers is examined. In a…
Strong electric fields can be used to align molecules. However, a non-polar molecule such as H$_2$ has no preference for its orientation. There are thus two equivalent configurations with equal energy separated by a potential-energy…
We calculate the tunneling current for a bilayer quantum Hall system in the interlayer incoherent regime. In order to capture the strong correlation effects we model the layers as two Wigner crystals coupled through interlayer Coulomb…
We present a simple model of composite particle tunnelling through a rectangular potential barrier in presence of magnetic field. The exact numerical solution of the problem is provided and the applicability to real physical situations is…
We present a semiclassical study of a transport process, the tunneling, in the presence of a magnetic field and a dissipative environment. We have found that the problem can be mapped onto an effective one-dimensional one, and the tunneling…
A quantum statistical theory of spin-dependent tunneling through asymmetric magnetic double barrier junctions is presented which describes $both$ ballistic and diffuse tunneling by a single analytical expression. It is evidenced that the…
The WKB and instanton answers for the tunnel splitting of the ground state in a symmetric double well potential are both reduced to an expression involving only the functionals of the potential, without the need for solving any auxilliary…
Traditionally quantum tunneling in a static SQUID is studied on the basis of a classical trajectory in imaginary time under a two-dimensional potential barrier. The trajectory connects a potential well and an outer region crossing their…
The tunneling splitting of the energy levels of a ferromagnetic particle in the presence of an applied magnetic field - previously derived only for the ground state with the path integral method - is obtained in a simple way from…