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Related papers: Magnetic Double-Wells: Lower Bounds on Tunneling

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We consider a particle bound to a two-dimensional plane and a double well potential, subject to a perpendicular uniform magnetic field . The energy difference between the lowest two eigenvalues--the eigenvalue splitting--is related to the…

Mathematical Physics · Physics 2022-01-25 Charles L. Fefferman , Jacob Shapiro , Michael I. Weinstein

We present a magnetic double-well Hamiltonian where the tunneling between the two wells vanishes, as recently announced.

Mathematical Physics · Physics 2025-09-04 Charles L. Fefferman , Jacob Shapiro , Michael I. Weinstein

We present new results on quantum tunneling between deep potential wells, in the presence of a strong constant magnetic field. We construct a family of double well potentials containing examples for which the low-energy eigenvalue splitting…

Mathematical Physics · Physics 2025-01-03 Charles L. Fefferman , Jacob Shapiro , Michael I. Weinstein

Inspired by a recent paper$^*$ by C. Fefferman, J. Shapiro and M. Weinstein, we investigate quantum tunneling for a Hamiltonian with a symmetric double well and a uniform magnetic field. In the simultaneous limit of strong magnetic field…

Mathematical Physics · Physics 2023-09-06 B. Helffer , A. Kachmar

We report tunneling phenomena in double In$_{0.53}$Ga$_{0.47}$As quantum-well structures that are at odds with the conventional parallel-momentum-conserving picture of tunneling between two-dimensional systems. We found that the tunneling…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Y. Lin , J. Nitta , ; A. K. M. Newaz , W. Song , E. E. Mendez

The two-dimensional magnetic Laplacian is considered. We calculate the leading term of the splitting between the first two eigenvalues of the operator in the semiclassical limit under the assumption that the magnetic field does not vanish…

Mathematical Physics · Physics 2025-02-25 Søren Fournais , Yannick Guedes Bonthonneau , Léo Morin , Nicolas Raymond

We provide a semiclassical theory of tunneling decay in a magnetic field and a three-dimensional potential of a general form. Because of broken time-reversal symmetry, the standard WKB technique has to be modified. The decay rate is found…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 T. Sharpee , M. I. Dykman , P. M. Platzman

Quantum tunneling between two potential wells in a magnetic field can be strongly increased when the potential barrier varies in the direction perpendicular to the line connecting the two wells and remains constant along this line. An…

Quantum Physics · Physics 2009-11-11 B. Ivlev

This article is devoted to the semiclassical spectral analysis of the magnetic Laplacian in two dimensions. Assuming that the magnetic field is positive and has two symmetric radial wells, we establish an accurate tunnelling formula, that…

Spectral Theory · Mathematics 2023-08-09 Søren Fournais , Léo Morin , Nicolas Raymond

We study the Coulomb pseudogap for tunneling into the two-dimensional electron system of high-mobility (Al,Ga)As/GaAs heterojunctions subjected to a quantizing magnetic field at filling factor $\nu \leq 1$. Tunnel current-voltage…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 E. V. Deviatov , A. A. Shashkin , V. T. Dolgopolov , W. Hansen , M. Holland

We revisit the problem of quantum tunneling for a particle moving in the continuum, and in the absence of a magnetic field. In all spatial dimensions, we extend previous results to the case where the single-well potential satisfies…

Mathematical Physics · Physics 2025-06-17 Charles L. Fefferman , Jacob Shapiro , Michael I. Weinstein

The conductance and tunnel magneto-resistance (TMR) of the double barrier magnetic tunnel junction with spin-valve sandwich (F/P/F) inserted between two insulating barrier, are theoretically investigated. It is shown, that resonant…

Condensed Matter · Physics 2009-11-10 N. Ryzhanova , G. Reiss , F. Kanjouri , A. Vedyayev

In this paper, we attempt the theoretical modeling of the magnetic tunnel junctions with embedded magnetic and nonmagnetic nanoparticles (NPs). A few abnormal tunnel magnetoresistance (TMR) effects, observed in related experiments, can be…

Mesoscale and Nanoscale Physics · Physics 2018-07-04 Arthur Useinov , Niazbeck Useinov , Lin-Xiu Ye , Te-Ho Wu , Chih-Huang Lai

We study resonant tunnelling through double-barrier structures under an applied bias voltage, in which nonlinearities due to self-interaction of electrons in the barrier regions are included. As an approximation, we concern ourselves with…

Condensed Matter · Physics 2009-10-22 Enrique Diez , Francisco Dominguez-Adame , Angel Sánchez

A three barrier resonant tunneling structure in which the two quantum wells are formed by a dilute magnetic semiconductor material (ZnMnSe) with a giant Zeeman splitting of the conduction band is theoretically investigated. Self-consistent…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Christian Ertler , Jaroslav Fabian

For an asymmetric double-well potential system, it is shown that, if the potential is quadratic until it reaches several times of the zero-point energies from the bottoms in each well, the energy eigenvalues of the low lying excited states…

Quantum Physics · Physics 2015-03-18 Dae-Yup Song

Puzzling observations of both thermal and dielectric responses in multi-silicate glasses at low temperatures $T$ to static magnetic fields $B$ have been reported in the last decade and call for an extension of the standard two-level systems…

Disordered Systems and Neural Networks · Physics 2015-05-13 Giancarlo Jug

An asymmetric double-well potential is considered, assuming that the minima of the wells are quadratic with a frequency $\omega$ and the difference of the minima is close to a multiple of $\hbar \omega$. A WKB wave function is constructed…

Quantum Physics · Physics 2011-04-13 Dae-Yup Song

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…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 T. Barabash-Sharpee , M. I. Dykman , P. M. Platzman

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…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 O. E. Raichev , P. Vasilopoulos
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