相关论文: Tunneling effects between tori in double wells
We consider coherent tunneling of one-dimensional model systems in non-cyclic or cyclic symmetric double well potentials. Generic potentials are constructed which allow for analytical estimates of the quantum dynamics in the…
We report on two sub-band transport in double gate SiO$_2$-Si-SiO$_2$ quantum well with 14 nm thick Si layer at 270 mK. At symmetric well potential the experimental sub-band spacing changes monotonically from 2.3 to 0.3 meV when the total…
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.…
Tunnel-injection lasers promise various advantages in comparison to conventional laser designs. In this paper, we present a theoretical analysis for the physics of the tunnel-injection process in quantum-dot based laser devices. We describe…
Motivated by the analysis of the tunneling effect for the magnetic Laplacian, we introduce an abstract framework for the spectral reduction of a self-adjoint operator to a hermitian matrix. We illustrate this framework by three…
We report on first experimental signatures for chaos-assisted tunneling in a two-dimensional annular billiard. Measurements of microwave spectra from a superconducting cavity with high frequency resolution are combined with electromagnetic…
We suggest a theory of internal coherent tunneling in the pseudogap region where the applied voltage is below the free electron gap. We consider quasi 1D systems where the gap is originated by a lattice dimerization like in polyacethylene,…
In this theoretical work, we study a double quantum dot interacting strongly with a microcavity, while undergoing resonant tunneling. Effects of interdot tunneling on the light-matter hybridized states are determined, and tunability of…
We consider tunneling through two point contacts between two edges of Quantum Hall liquids of different filling factors $\nu_{0,1}=1/ (2m_{0,1}+1)$ with $m_0-m_1\equiv m>0$. Properties of the antidot formed between the point contacts in the…
We present a path - integral approach to treat a 2D model of a quantum bifurcation. The model potential has two equivalent minima separated by one or two saddle points, depending on the value of a continuous parameter. Tunneling is…
It is shown how the model which was introduced by Mouchet (2008 Eur. J. Phys. 29 1033) allows one to mimic the quantum tunnelling between two symmetric one-dimensional wells.
We investigate the effects induced by spin polarization in the contacts attached to a serial double quantum dot. The polarization generates effective magnetic fields and suppresses the Kondo effect in each dot. The super-exchange…
An effect of paramagnetic impurity located in a vicinity of a quantum well (QW) on spin polarization of the carriers in the QW is analyzed theoretically. Within approach of Bardeen's tunneling Hamiltonian the problem is formulated in terms…
In a two dimensional free electron gas (2DEG) subjected to a perpendicular spatially varying magnetic field, the classical paths of electrons are snake-like trajectories that weave along the line where the field crosses zero. But quantum…
The path is explored between one-dimensional scattering through Dirac-$\delta$ walls and one-dimensional quantum field theories defined on a finite length interval with Dirichlet boundary conditions. It is found that two $\delta$'s are…
An asymmetric double quantum wells (QWs) structure with resonant tunneling is suggested to achieve high efficient four wave mixing (FWM). We analytically demonstrate that the resonant tunneling can induce high efficient mixing wave in such…
We consider tunneling in a hybrid system consisting of a superconductor with two or more probe electrodes which can be either normal metals or polarized ferromagnets. In particular we study transport at subgap voltages and temperatures.…
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 study the spectral properties of a Schr\"odinger operator, in presence of a confining potential given by the distance squared from a fixed compact potential well. We prove continuity estimates on both the eigenvalues and the eigenstates,…
A logarithmic type Lieb-Thirring inequality for two-dimensional Schroedinger operators is established. The result is applied to prove spectral estimates on trapped modes in quantum layers.