Related papers: Zero modes on cosmic strings in an external magnet…
The zero modes and current carrying capability of a cosmic string formed at one phase transition can be modified at subsequent phase transitions. A new, generalised index theorem is derived that is applicable to theories with multiple phase…
Grand unified theories can admit cosmic strings with fermion zero modes. Such zero modes result in the string being current-carrying and the formation of stable remnants, vortons. However, the string zero modes do not automaticall survive…
The stability of fermionic charge carriers on cosmic strings is considered. We show that neutral fermion currents in cosmic strings are always chiral or time-like, in contrast to the case of bosonic currents. The spectrum of bound states on…
We study the scattering of fermions off a finite width kink wall during the electroweak phase transition in the presence of a background hypermagnetic field. We derive and solve the Dirac equation for such fermions and compute the…
We provide a thorough exposition, including technical and numerical details, of previously published results on the quantum stabilization of cosmic strings. Stabilization occurs through the coupling to a heavy fermion doublet in a reduced…
We present a theoretical study of spin-dependent transport through a ferromagnetic domain wall. With an increase of the number of components of the exchange coupling, we have observed that the variance of the conductance becomes half. As…
We consider a semiconductor in a non-equilibrium steady state, with a dc current. On top of the stationary carrier motion there are fluctuations. It is shown that the stationary motion of the carriers (i.e., their drift) can have a profound…
We study some consequences of dimensionally reducing systems with massless fermions and Abelian gauge fields from 3+1 to 2+1 dimensions. We first consider fermions in the presence of an external Abelian gauge field. In the reduced theory,…
We investigate what becomes of the translational zero-mode of a five-dimensional domain wall in the presence of gravity, studying the scalar perturbations of a thick gravitating domain wall with AdS asymptotics and a well-defined…
The impact of free charges on the local pressure on a charged ferroelectric domain wall produced by an electric field has been analyzed. A general formula for the local pressure on a charged domain wall is derived considering full or…
We study the dynamics of a ferromagnetic domain wall driven by an external magnetic field through a disordered medium. The avalanche-like motion of the domain walls between pinned configurations produces a noise known as the Barkhausen…
The equation of state for a superconducting cosmic string whose current is due to fermionic zero modes is derived analytically in the case where the back-reaction of the fermions to the background is neglected. It is first shown that the…
We find exact, simple solutions to the Proca version of Maxwell's equations with magnetic sources. Several properties of these solutions differ from the usual case of magnetic charge with a massless photon: (i) the string singularities of…
We study the self-interaction effects for the Dirac particle moving in an external field created by static charges in (1+1)-dimensions. Assuming that the total electric charge of the system vanishes, we show that the asymptotically linearly…
The semiclassical Boltzmann transport equation of charged, massive fermions in a rotating frame of reference, in the presence of external electromagnetic fields is solved in the relaxation time approach to establish the distribution…
We investigate metal-insulator transitions on an interacting two-dimensional Dirac fermion system using the determinant quantum Monte Carlo method. The interplay between Coulomb repulsion, disorder and magnetic fields, drives the otherwise…
Zero-mass lines result in appearance of linear dispersion modes for Dirac fermions. These modes play an important role in various physical systems. However, a Dirac fermion may not precisely follow a single zero-mass line, due to either…
The plasmon frequency in standard electron gases with a parabolic single-particle dispersion is a purely classical quantity that is not sensitive to electron interactions or the equation of state. We demonstrate that this canonical result…
Recent developments in string theory suggest that cosmic strings could be formed at the end of brane inflation. Supergravity provides a realistic model to study the properties of strings arising in brane inflation. Whilst the properties of…
We theoretically examine a cross effect of magnetic field and charge current on antiferromagnetic domain wall dynamics. Since antiferromagnetic materials are largely insensitive to external magnetic fields in general, charge current has…