scholarly journals A SIMPLE DIRAC WAVE FUNCTION FOR A COULOMB POTENTIAL WITH LINEAR CONFINEMENT

1999 ◽  
Vol 14 (34) ◽  
pp. 2409-2411 ◽  
Author(s):  
JERROLD FRANKLIN

A simple analytical solution is found to the Dirac equation for the combination of a Coulomb potential with a linear confining potential. An appropriate linear combination of Lorentz scalar and vector linear potentials, with the scalar part dominating, can be chosen to give a simple Dirac wave function. The binding energy depends only on the Coulomb strength and is not affected by the linear potential. The method works for the ground state, or for the lowest state with l=j-1/2, for any j.

2000 ◽  
Vol 15 (27) ◽  
pp. 4355-4360
Author(s):  
ANTONIO SOARES DE CASTRO ◽  
JERROLD FRANKLIN

Exact solutions are found for the Dirac equation for a combination of Lorentz scalar and vector Coulombic potentials with additional non-Coulombic parts. An appropriate linear combination of Lorentz scalar and vector non-Coulombic potentials, with the scalar part dominating, can be chosen to give exact analytic Dirac wave functions. The method works for the ground state or for the lowest orbital state with l=j-½, for any j.


2021 ◽  
pp. 1-26
Author(s):  
Tianfang Wang ◽  
Wen Zhang ◽  
Jian Zhang

In this paper we study the Dirac equation with Coulomb potential − i α · ∇ u + a β u − μ | x | u = f ( x , | u | ) u , x ∈ R 3 where a is a positive constant, μ is a positive parameter, α = ( α 1 , α 2 , α 3 ), α i and β are 4 × 4 Pauli–Dirac matrices. The Dirac operator is unbounded from below and above so the associate energy functional is strongly indefinite. Under some suitable conditions, we prove that the problem possesses a ground state solution which is exponentially decay, and the least energy has continuous dependence about μ. Moreover, we are able to obtain the asymptotic property of ground state solution as μ → 0 + , this result can characterize some relationship of the above problem between μ > 0 and μ = 0.


2020 ◽  
Vol 1 ◽  
pp. 187
Author(s):  
C. G. Koutroulos ◽  
M. E. Grypeos

The Dirac equation with potentials having attractive and repulsive parts is con­ sidered in a simplified model and approximate semiempirical mass formulae for the ground state binding energy of a Λ in hypernuclei are derived and discussed.


2013 ◽  
Vol 475-476 ◽  
pp. 1355-1358
Author(s):  
Arnold Abramov

In this paper we present exact numerical procedure to calculate the binding energy and wave function of impurity states in a quantum dot with parabolic confinement. The developed method allows control the accuracy of obtained results, as well as calculates the characteristics of not only ground state, but also of the excited states. Comparison of our results with data obtained by other methods is in quantitative and qualitative agreement. We studied the effects of impurity position on the binding energy.


2012 ◽  
Vol 09 (04) ◽  
pp. 1250026 ◽  
Author(s):  
MAYEUL ARMINJON ◽  
FRANK REIFLER

In a Minkowski spacetime, one may transform the Dirac wave function under the spin group, as one transforms coordinates under the Poincaré group. This is not an option in a curved spacetime. Therefore, in the equation proposed independently by Fock and Weyl, the four complex components of the Dirac wave function transform as scalars under a general coordinate transformation. Recent work has shown that a covariant complex four-vector representation is also possible. Using notions of vector bundle theory, we describe these two representations in a unified framework. We prove theorems that relate together the different representations and the different choices of connections within each representation. As a result, either of the two representations can account for a variety of inequivalent, linear, covariant Dirac equations in a curved spacetime that reduce to the original Dirac equation in a Minkowski spacetime. In particular, we show that the standard Dirac equation in a curved spacetime, with any choice of the tetrad field, is equivalent to a particular realization of the covariant Dirac equation for a complex four-vector wave function.


2007 ◽  
Vol 22 (18) ◽  
pp. 3123-3130
Author(s):  
V. V. BONDARCHUK ◽  
I. M. SHVAB ◽  
A. V. KATERNOGA

The ground state wave function and the energy term of a relativistic electron moving in the field of two fixed centers, when interaction of this particle with centers is described by two Coulomb and two Coulomb-like scalar potentials are calculated analytically by the LCAO method. Dependence of electron binding energy from value of scalar coupling constant was investigated using obtained analytic results.


2012 ◽  
Vol 15 ◽  
pp. 224-231 ◽  
Author(s):  
K. H. AHARONYAN ◽  
E. M. KAZARYAN

We theoretically investigate excitonic effects on the optical properties of quasi-two dimensional realistic EuS/PbS/EuS finite confining potential quantum well. The strong contrast of material parameter’s across the well interfaces and the characteristic band-nonparabolicity effect of lead salt semiconductor are taken into account. In presence of medium polarization a feasibility of the screened Coulomb potential in quantum well is examined and appropriate screening radius is revealed for the first time. The screened binding energy investigated while a variational approach has been used. Depend on the realistic nanostructure specifics a monotonic decrease of the enhanced binding energy is received when in-plane carrier density/temperature ratio parameter increases. Exciton absorption spectra near the band edge within the effective-mass approximation is examined. Coulomb potential having a cutoff type is used, that efficiently represented the potential in the realistic quantum well. Screened exciton factor, which is the absorption intensity enhancement of the unbound (continuum) exciton states that are located above the band edge, is used. Plot of the dependence of the exciton factor on the exciton pair energy is given.


2000 ◽  
Vol 15 (10) ◽  
pp. 683-693
Author(s):  
KANAD RAY ◽  
JISHNU DEY ◽  
MIRA DEY

A RHF method is used to calculate magnetic moment μ of Ω- using the Richardson potential. Unlike the mass of baryon, μ is very sensitive to the detailed structure of the model since it depends on the wave function. Given any quark–quark (qq) potential we have the RHF wave function for the ground state. We have developed a code for expanding this Dirac wave function in terms of two sets of oscillators. To fit both the mass and magnetic moment simultaneously we find that it is essential to separate out the confining part from the asymptotically free part of the potential and use different parameters for each part. The best fitted results from our model are in good agreement with experiment.


2012 ◽  
Vol 26 (17) ◽  
pp. 1250108
Author(s):  
HAI HUANG ◽  
XIA HUANG

Two-dimensional massive Dirac equation in both potential well and linear potential is discussed. We find that in the case of potential well, the bound states disappear from the spectrum for large enough potential depth. With the linear confining potential, we show that the Dirac equation presents no bound state. Both these results can be identified as fine examples of the Klein paradox. Applications to graphene systems are also discussed.


1994 ◽  
Vol 03 (03) ◽  
pp. 939-951
Author(s):  
G.J. PAPADOPOULOS ◽  
C.G. KOUTROULOS ◽  
M.E. GRYPEOS

The binding energy BΛ of a Λ-particle in hypernuclei is studied by means of the Dirac equation with attractive and repulsive potentials of rectangular shapes and of the same radius. The energy eigenvalue equation in this case is obtained analytically for every bound state, as well as the large and small component of the wave function (for given BΛ). A first attempt is also made to investigate the possibility of deriving in particular cases approximate analytic expressions of BΛ for the excited states. Using various least squares fittings, numerical results for the binding energy of the Λ are given and comparisons and comments are also made.


Sign in / Sign up

Export Citation Format

Share Document