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Related papers: Revisiting double Dirac delta potential

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We analyze here the energy states and associated wave functions available to a particle acted upon by a delta function potential of arbitrary strength and sign and fixed anywhere within a one-dimensional infinite well. We consider how the…

Quantum Physics · Physics 2010-08-03 T. B. Smith , D. A. Dubin , M. A. Hennings

In this brief review, we survey the problem of electrostatic confinement of massless Dirac particles, via a number of exactly solvable one- and two-body models. By considering bound states at zero energy, we present a route to obtain truly…

Mesoscale and Nanoscale Physics · Physics 2019-09-24 C. A. Downing , M. E. Portnoi

We study the spectrum, eigenstates and transport properties of a simple $\mathcal{P}\mathcal{T}$-symmetric model consisting in a finite, complex, square well potential with a delta potential at the origin. We show that as the strength of…

Quantum Physics · Physics 2024-12-18 Francisco Ricardo Torres Arvizu , Adrian Ortega , Hernán Larralde

The construction of Dirac delta type potentials has been achieved with the use of the theory of self adjoint extensions of non-self adjoint formally Hermitian (symmetric) operators. The application of this formalism to investigate the…

We discuss electron scattering in a one-dimensional delta barrier potential with either time-dependent coupling constant (classical model) or a coupling constant that is linear in a boson coordinate (quantum model). We find an exact…

Mesoscale and Nanoscale Physics · Physics 2015-06-24 T. Brandes , J. Robinson

We analyze the dynamical evolution of the resonant tunneling of an ensemble of electrons through a double barrier in the presence of the self-consistent potential created by the charge accumulation in the well. The intrinsic nonlinearity of…

Mesoscale and Nanoscale Physics · Physics 2016-08-31 Carlo Presilla , Giovanni Jona-Lasinio , Federico Capasso

It is known that the perfect absorption of two identical waves incident on a complex potential from left and right can occur at a fixed real energy and that the time-reversed setting of this system would act as a laser at threshold at the…

Quantum Physics · Physics 2014-09-26 Zafar Ahmed

The general solution of the Dirac equation for quasi-two-dimensional electrons confined in an asymmetric quantum well, is found. The energy spectrum of such a system is exactly calculated using special unitary transformation and shown to…

Mesoscale and Nanoscale Physics · Physics 2016-05-04 A. A. Eremko , L. S. Brizhik , V. M. Loktev

We study an anti-symmetric (square) well and barrier potential of depth/height $(V_0)$ placed between two rigid walls. Unlike the usual double-well, here the closely lying sub-barrier doublets need not be the lowest ones in the spectrum.…

Quantum Physics · Physics 2014-06-19 Zafar Ahmed , Shashin Pavaskar , Indresh Yadav , Tanayveer Bhatia

We present an exact quantization condition for the time independent solutions (energy eigenstates) of the one-dimensional Dirac equation with a scalar potential well that gives only two `effective' turning points (defined by the roots of…

Quantum Physics · Physics 2016-06-06 Siddhant Das

Analyzing the point spectrum, i.e. bound state energy eigenvalue, of the Dirac delta function in two and three dimensions is notoriously difficult without recourse to regularization or renormalization, typically both. The reason for this in…

Quantum Physics · Physics 2023-12-11 Michael Maroun

In this paper we construct $\mathcal{N}=2$ supersymmetric (SUSY) quantum mechanics over several configurations of Dirac-$\delta$ potentials from one single delta to a Dirac " comb \rq\rq. We show in detail how the building of supersymmetry…

Mathematical Physics · Physics 2015-01-29 J. Mateos Guilarte , J. M. Munoz Castaneda , A. Moreno Mosquera

Two port s-matrix for a complex PT-symmetric potential may have uni-modular eigenvalues. If this happens for all energies, there occurs a perfect emission of waves at both ends. We call this phenomenon transparency which is distinctly…

Quantum Physics · Physics 2016-01-07 Zafar Ahmed , Joseph Amal Nathan , Dona Ghosh

Existing investigations of the anomalous Hall effect i.e. a current flowing transverse to the electric field in the absence of an external magnetic field) are concerned with the transport current. However, for many applications one needs to…

Mesoscale and Nanoscale Physics · Physics 2019-09-11 P. G. Silvestrov , P. Recher

We reanalyze the problem of a 1D Dirac single particle colliding with the electrostatic potential step of height $V_{0}$ with a positive incoming energy that tends to the limit point of the so-called Klein energy zone, i.e., $E\rightarrow…

Quantum Physics · Physics 2023-03-01 Salvatore De Vincenzo

We investigate $L^1\to L^\infty$ dispersive estimates for the massless two dimensional Dirac equation with a potential. In particular, we show that the Dirac evolution satisfies the natural $t^{-\frac12}$ decay rate, which may be improved…

Analysis of PDEs · Mathematics 2019-03-05 Burak Erdogan , Michael Goldberg , William R. Green

In 1928, P. Dirac proposed a new wave equation to describe relativistic electrons. Shortly afterwards, O. Klein solved a simple potential step problem for the Dirac equation and stumbled upon an apparent paradox - the potential becomes…

We study the tunneling through delta and double delta potentials in fractional quantum mechanics. After solving the fractional Schr\"odinger equation for these potentials, we calculate the corresponding reflection and transmission…

Mathematical Physics · Physics 2015-05-20 Edmundo Capelas de Oliveira , Jayme Vaz

Spectral singularities and the coherent perfect absorption are two interrelated concepts that have originally been introduced and studied for linear waves interacting with complex potentials. In the meantime, the distinctive asymptotic…

Pattern Formation and Solitons · Physics 2020-10-22 Dmitry A. Zezyulin , Vladimir V. Konotop

It is shown that a potential consisting of three Dirac's delta functions on the line with disappearing distances can give rise to the discontinuity in wave functions with the proper renormalization of the delta function strength. This can…

Quantum Physics · Physics 2009-09-25 Taksu Cheon , T. Shigehara