Related papers: Quantum tunneling and its absence in deep wells an…
Magnetotunneling spectroscopy was employed to probe the confinement in vertical Si/Ge double-barrier resonant tunneling diodes with regularly distributed Ge quantum dots. Their current-voltage characteristics reveal a step-like behavior in…
We study the photoluminescence from a near-surface quantum well in the regime of ambipolar tunneling to the surface states. Under steady-state excitation an electric field develops self-consistently due to the condition of equal tunneling…
The quantum tunneling of the magnetization vector between excited levels are studied theoretically in single-domain ferromagnetic nanoparticles with biaxial crystal symmetry placed in an external magnetic field at an arbitarily directed…
We study the one dimensional potentials in q space and the new features that arise. In particular we show that the probability of tunneling of a particle through a barrier or potential step is less than the one of the same particle with the…
We study the tunneling of a two-level atom in a double well potential while the atom is coupled to a single electromagnetic field mode of a cavity. The coupling between internal and external degrees of freedom, due to the mechanical effect…
We have studied the electrical conductivity of the electron gas in parallel electric and magnetic fields directed along the plane of a parabolic quantum well (across the profile of the potential). We found a general expression for the…
We examine the magnetic field driven insulator-quantum Hall-insulator transitions of the two dimensional hole gas in a Ge/SiGe quantum well. We observe direct transitions between low and high magnetic field insulators and the $\nu=1$…
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…
We study macroscopic quantum coherence in antiferromagnetic molecular magnets in the presence of magnetic fields. Such fields generate artificial tunnel barriers with externally tunable strength. We give detailed semi-classical predictions…
While the dynamics for three-dimensional axially symmetric two-electron quantum dots with parabolic confinement potentials is in general non-separable we have found an exact separability with three quantum numbers for specific values of the…
We employ magnetocapacitance and far-infrared spectroscopy techniques to study the spectrum of the double-layer electron system in a parabolic quantum well with a narrow tunnel barrier in the centre. For gate-bias-controlled asymmetric…
We investigate the {\em nonlinearity-assisted quantum tunneling} and formation of nonlinear collective excitations in a matter-wave interferometer, which is realised by the adiabatic transformation of a double-well potential into a…
The tunneling conductance between two parallel 2D electron systems has been measured in a regime of strong interlayer Coulomb correlations. At total Landau level filling $\nu_T=1$ the tunnel spectrum changes qualitatively when the boundary…
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…
Renormalized tunnel splitting with a finite distribution in the biaxial spin model for molecular magnets is obtained by taking into account the dipolar interaction of enviromental spins. Oscillation of the resonant tunnel splitting with a…
The vacuum cavity mode induces a potential barrier and a well when an ultra-slow excited atom enters the interaction region so that it can be reflected or transmitted with a certain probability. We demonstrate here that a slow-velocity…
We analyze inelastic cotunneling through an interacting quantum dot subject to an ambient magnetic field in the weak tunneling regime under a non-adiabatic time-dependent bias-voltage. Our results clearly exhibit photon-assisted satellites…
We allow a scalar field on a flat FLRW background metric to tunnel between two degenerate vacua. The resulting true vacuum state then violates the Null Energy Condition, and the corresponding homogeneous fluid induces a bounce, after which…
In In_xGa_{1-x}As/n-GaAs double quantum wells (DQWs) containing an electron gas, the magnetoresistance (MR) peculiarities under parallel magnetic fields caused by the passing of the tunnel gap edges through the Fermi level are revealed.…
Within the framework of fractional quantum mechanics, an exact solution has been found for the energy spectrum of a quantum particle confined in a quantum well - a symmetric one-dimensional finite potential well. A simple graphical…