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Papers by Gabriela Murguia
Journal of Physics A: Mathematical and General, 2003
arxiv.org
We derive the exact Foldy-Wouthuysen transformation for Dirac fermions in a time independent exte... more We derive the exact Foldy-Wouthuysen transformation for Dirac fermions in a time independent external electromagnetic field in the basis of the Ritus eigenfunctions, namely the eigenfunctions of the operator (γ · Π) 2 , with Π µ = p µ − eA µ . In this basis, the transformation acquires a free form involving the dynamical quantum numbers induced by the field.
Journal of Physics-condensed Matter, 2012
Using irreducible and reducible representations of the Dirac matrices, we study the two-and four-... more Using irreducible and reducible representations of the Dirac matrices, we study the two-and four-component quantum mechanical supersymmetric (SUSY) theories for ultrarelativistic fermions in (2+1)-dimensions ("graphinos") in a background uniform magnetic field perpendicular to their plane of motion. We then consider ordinary and parity-violating mass terms and identify the former as a soft SUSY-breaking term and the later as the hard SUSY-breaking one.
Advances in Science …, Jan 1, 2011
Page 1. A Multiband Model for LaO1-xFxFeAs Gabriela Murguía a , S. Orozco b , MA Ortiz c , RM Mén... more Page 1. A Multiband Model for LaO1-xFxFeAs Gabriela Murguía a , S. Orozco b , MA Ortiz c , RM Méndez-Moreno d and P. de la Mora e Departamento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de México, ...
Arxiv preprint arXiv:0903.0427, Jan 1, 2009
A well known example in quantum electrodynamics (QED) shows that Coulomb scattering of unpolarize... more A well known example in quantum electrodynamics (QED) shows that Coulomb scattering of unpolarized electrons, calculated to lowest order in perturbation theory, yields a results that exactly coincides (in the non-relativistic limit) with the Rutherford formula. We examine an analogous example, the classical and perturbative quantum scattering of an electron by a magnetic field confined in an infinite solenoid of finite radius. The results obtained for the classical and the quantum differential cross sections display marked differences. While this may not be a complete surprise, one should expect to recover the classical expression by applying the classical limit to the quantum result. This turn not to be the case. Surprisingly enough, it is shown that the classical result can not be recuperated even if higher order corrections are included. To recover the classic correspondence of the quantum scattering problem a suitable non-perturbative methodology should be applied.
We study the dynamics of carriers in graphene subjected to an inhomogeneous magnetic field. For a... more We study the dynamics of carriers in graphene subjected to an inhomogeneous magnetic field. For a magnetic field with an hyperbolic profile the corresponding Dirac equation can be analyzed within the formalism of supersymmetric quantum mechanics, and leads to an exactly solvable model. We study in detail the bound spectra. For a narrow barrier the spectra is characterized by a few bands, except for the zero energy level that remains degenerated. As, the width of the barrier increases we can track the bands evolution into the degenerated Landau levels. In the scattering regime a simple analytical formula is obtained for the transmission coefficient, this result allow us to identify the resonant conditions at which the barrier becomes transparent.
Arxiv preprint arXiv: …, Jan 1, 2009
Arxiv preprint quant-ph/0407123, Jan 1, 2004
Arxiv preprint physics/0202020, Jan 1, 2002
Arxiv preprint arXiv:1008.4901, Jan 1, 2010
Journal of Physics A: Mathematical and General, 2003
arxiv.org
We derive the exact Foldy-Wouthuysen transformation for Dirac fermions in a time independent exte... more We derive the exact Foldy-Wouthuysen transformation for Dirac fermions in a time independent external electromagnetic field in the basis of the Ritus eigenfunctions, namely the eigenfunctions of the operator (γ · Π) 2 , with Π µ = p µ − eA µ . In this basis, the transformation acquires a free form involving the dynamical quantum numbers induced by the field.
Journal of Physics-condensed Matter, 2012
Using irreducible and reducible representations of the Dirac matrices, we study the two-and four-... more Using irreducible and reducible representations of the Dirac matrices, we study the two-and four-component quantum mechanical supersymmetric (SUSY) theories for ultrarelativistic fermions in (2+1)-dimensions ("graphinos") in a background uniform magnetic field perpendicular to their plane of motion. We then consider ordinary and parity-violating mass terms and identify the former as a soft SUSY-breaking term and the later as the hard SUSY-breaking one.
Advances in Science …, Jan 1, 2011
Page 1. A Multiband Model for LaO1-xFxFeAs Gabriela Murguía a , S. Orozco b , MA Ortiz c , RM Mén... more Page 1. A Multiband Model for LaO1-xFxFeAs Gabriela Murguía a , S. Orozco b , MA Ortiz c , RM Méndez-Moreno d and P. de la Mora e Departamento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de México, ...
Arxiv preprint arXiv:0903.0427, Jan 1, 2009
A well known example in quantum electrodynamics (QED) shows that Coulomb scattering of unpolarize... more A well known example in quantum electrodynamics (QED) shows that Coulomb scattering of unpolarized electrons, calculated to lowest order in perturbation theory, yields a results that exactly coincides (in the non-relativistic limit) with the Rutherford formula. We examine an analogous example, the classical and perturbative quantum scattering of an electron by a magnetic field confined in an infinite solenoid of finite radius. The results obtained for the classical and the quantum differential cross sections display marked differences. While this may not be a complete surprise, one should expect to recover the classical expression by applying the classical limit to the quantum result. This turn not to be the case. Surprisingly enough, it is shown that the classical result can not be recuperated even if higher order corrections are included. To recover the classic correspondence of the quantum scattering problem a suitable non-perturbative methodology should be applied.
We study the dynamics of carriers in graphene subjected to an inhomogeneous magnetic field. For a... more We study the dynamics of carriers in graphene subjected to an inhomogeneous magnetic field. For a magnetic field with an hyperbolic profile the corresponding Dirac equation can be analyzed within the formalism of supersymmetric quantum mechanics, and leads to an exactly solvable model. We study in detail the bound spectra. For a narrow barrier the spectra is characterized by a few bands, except for the zero energy level that remains degenerated. As, the width of the barrier increases we can track the bands evolution into the degenerated Landau levels. In the scattering regime a simple analytical formula is obtained for the transmission coefficient, this result allow us to identify the resonant conditions at which the barrier becomes transparent.
Arxiv preprint arXiv: …, Jan 1, 2009
Arxiv preprint quant-ph/0407123, Jan 1, 2004
Arxiv preprint physics/0202020, Jan 1, 2002
Arxiv preprint arXiv:1008.4901, Jan 1, 2010