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Hamiltonian self-adjoint extensions for (2+1)-dimensional Dirac particles

H. Falomir·P. A. G. Pisani
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Abstract

We study the stationary problem of a charged Dirac particle in (2+1) dimensions in the presence of a uniform magnetic field B and a singular magnetic tube of flux Phi = 2 pi kappa/e. The rotational invariance of this configuration implies that the subspaces of definite angular momentum l+1/2 are invariant under the action of the Hamiltonian H. We show that, for l different from the integer part of kappa, the restriction of H to these subspaces, H_l is essentially self-adjoint, while for l equal to the integer part of kappa, H_l admits a one-parameter family of self-adjoint extensions (SAE). In the later case, the functions in the domain of H_l are singular (but square-integrable) at the origin, their behavior being dictated by the value of the parameter gamma that identifies the SAE. We also determine the spectrum of the Hamiltonian as a function of kappa and gamma, as well as its closure.

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H. Falomir, P. A. G. Pisani. 2001-04-19. Hamiltonian self-adjoint extensions for (2+1)-dimensional Dirac particles. https://doi.org/10.1088/0305-4470%2F34%2F19%2F312

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