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A. Pérez Martínez

Publications and source records attributed to A. Pérez Martínez.

23 records · Page 2Linked to original sources
arXiv2011

2D massless QED Hall half-integer conductivity and graphene

Starting from the photon self-energy tensor in a magnetized medium, the 3D complete antisymmetric form of the conductivity tensor is found in the static limit of a fermion system $C$ non-invariant under fermion-antifermion exchange. The massless relativistic 2D fermion limit in QED is derived by using the compactification along the dimension parallel to the magnetic field. In the static limit and at zero temperature the main features of quantum Hall effect (QHE) are obtained: the half-integer QHE and the minimum value proportional to $e^2/h$ for the Hall conductivity . For typical values of graphene the plateaus of the Hall conductivity are also reproduced.

cond-mat.mes-hall↗
arXiv2010

Magnetic field effects on some astrophysical properties of Quark Stars

This thesis aims to study how amending certain astrophysical observable of quark stars due to presence of magnetic field. To do this we need to obtain Equation of State (EOS) and consider the stability of Strange Quark Matter (made up of quarks u, d and s) cold dense and magnetized in stellar equilibrium (beta equilibrium, conservation of the baryonic number and charge neutrality). We will work using the phenomenological MIT Bag model. The stability of the Magnetized Strange Quark Matter (MSQM) is studied taking into account the variation of parameters from the model: s quark mass, baryonic density, magnetic field and the Bag parameter. Results obtained were compared with those of magnetized normal quark matter (only u and d quarks in beta equilibrium) as well as the Strange Quark Matter (SQM). It is found that the energy per baryon decreases with the increasing magnetic field which implies that the MSQM is more stable than SQM. The Equations of State previously obtained are used to obtain stable configurations of magnetized strange stars checking that the magnetic field helps to reduce Mass-Radius (M-R) ratio of the star.

astro-ph.HE↗
arXiv2004

Exploding Bose-Einstein condensates and collapsing neutron stars driven by critical magnetic fields

The problem of a condensate of a relativistic neutral vector boson gas constituted of particles bearing a magnetic moment is discussed. Such a vector boson system is expected to be formed either by parallel spin-pairing of neutrons in a sufficiently strong magnetic field, or by neutral atoms under specific conditions of magnetic field strength and density. A strong self-magnetization arises due to a Bose-Einstein-like condensation. Then the system, which may resemble the superfluid said to exist in the core of neutron stars, becomes more unstable under transverse collapse than the ordinary fermion gas. In the nonrelativistic limit of laboratory conditions, an analogy with the behavior of exploding Bose-Einstein condensates for critical values of magnetic field strength and particle density; reported by several authors, is briefly discussed.

cond-mat.stat-mech↗
arXiv1997

Neutrinos in Strong Magnetic Fields

We compute the dispersion curves for neutrinos propagating in an extremely dense electroweak plasma, in the presence of very strong magnetic fields of order $B \le M_W^2/e$. The neutrino self-energy is calculated in the one-loop approximation. We consider only contributions of the first Landau level to the propagator of the W-bosons, and distinguish between motion parallel or perpendicular to the external magnetic field. We find that the neutrino dispersion curve for parallel propagation to the field suggests a superfluid behavior. An interesting analogy with fractional QHE is pointed out. We obtain a neutrino effective mass which increases with the magnetic field.

hep-ph↗