Fermionic current densities induced by magnetic flux in a conical space with a circular boundary

Mello, E. R. Bezerra de; Bezerra, V. B.; Saharian, A. A.; Bardeghyan, V. M.

doi:10.1103/physrevd.82.085033

Cited by 66 publications

(110 citation statements)

References 80 publications

Supporting

Mentioning

105

Contrasting

Order By: Relevance

“…The wave functions (2.16) are eigenfunctions of the projection of total angular momentum operator along the cosmic string, 19) with the eigenvalues j + α. The constants C (±) σ in (2.16) are determined by the orthonormalization condition 20) where γ is the determinant of the spatial metric tensor.…”

Section: Geometry and The Fermionic Modesmentioning

confidence: 99%

“…The azimuthal current density for scalar and fermionic fields, induced by a magnetic flux in the geometry of a straight cosmic string, has been investgated in [14]- [18]. The fermionic current induced by a magnetic flux in a (2 + 1)-dimensional conical spacetime with a circular boundary has been analyzed in [19]. The compactification of the cosmic string along its axis may lead to the appearance of the axial current density [17,18] (for the vacuum expectation value of the current density in models with compact dimensions see [20] in the case of flat background geometry and [21,22] for de Sitter and anti-de Sitter bulks).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Finite temperature fermionic charge and current densities induced by a cosmic string with magnetic flux

Mohammadi

Mello

Saharian

2015

J. Phys. A: Math. Theor.

View full text Add to dashboard Cite

We investigate the finite temperature expectation values of the charge and current densities for a massive fermionic field with nonzero chemical potential, µ, in the geometry of a straight cosmic string with a magnetic flux running along its axis. These densities are decomposed into the vacuum expectation values and contributions coming from the particles and antiparticles. The charge density is an even periodic function of the magnetic flux with the period equal to the quantum flux and an odd function of the chemical potential. The only nonzero component of the current density corresponds to the azimuthal current. The latter is an odd periodic function of the magnetic flux and an even function of the chemical potential. At high temperatures, the parts in the charge density and azimuthal current induced by the planar angle deficit and magnetic flux are exponentially small. The asymptotic behavior at low temperatures crucially depends whether the value |µ| is larger or smaller than the mass of the field quanta, m. For |µ| < m the charge density and the contributions into the azimuthal current coming from the particles and antiparticles are exponentially suppressed at low temperatures. In the case |µ| > m, the charge and current densities receive two contributions coming from the vacuum expectation values and from particles or antiparticles (depending on the sign of chemical potential). At large distances from the string the latter exhibits a damping oscillatory behavior with the amplitude inversely proportional to the square of the distance.

show abstract

Section: Geometry and The Fermionic Modesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Finite temperature fermionic charge and current densities induced by a cosmic string with magnetic flux

Mohammadi

Mello

Saharian

2015

J. Phys. A: Math. Theor.

View full text Add to dashboard Cite

show abstract

“…Note that the radius of the magnetic flux should also be taken to zero. For j + α = 0 one has 22) and, hence, the part (4.21) vanishes as a 2|j+α| . For half-odd integer values of α, the exceptional case corresponds to the mode with j = −α.…”

Section: Charge Densitymentioning

confidence: 99%

“…[22]: (4.32) Similarly to the boundary-induced contributions, this part is an odd function of the parameter α 0 . For a massless field the boundary-free contribution in the charge density vanishes for r = 0.…”

Section: Charge Densitymentioning

confidence: 99%

See 1 more Smart Citation

Induced fermionic charge and current densities in two-dimensional rings

2016

View full text Add to dashboard Cite

For a massive quantum fermionic field, we investigate the vacuum expectation values (VEVs) of the charge and current densities induced by an external magnetic flux in a two-dimensional circular ring. Both the irreducible representations of the Clifford algebra are considered. On the ring edges the bag (infinite mass) boundary conditions are imposed for the field operator. This leads to the Casimir type effect on the vacuum characteristics. The radial current vanishes. The charge and the azimuthal current are decomposed into the boundary-free and boundary-induced contributions. Both these contributions are odd periodic functions of the magnetic flux with the period equal to the flux quantum. An important feature that distinguishes the VEVs of the charge and current densities from the VEV of the energy density, is their finiteness on the ring edges. The current density is equal to the charge density for the outer edge and has the opposite sign on the inner edge. The VEVs are peaked near the inner edge and, as functions of the field mass, exhibit quite different features for two inequivalent representations of the Clifford algebra. We show that, unlike the VEVs in the boundary-free geometry, the vacuum charge and the current in the ring are continuous functions of the magnetic flux and vanish for half-odd integer values of the flux in units of the flux quantum. Combining the results for two irreducible representations, we also investigate the induced charge and current in parity and time-reversal symmetric models. The corresponding results are applied to graphene rings with the electronic subsystem described in terms of the effective Dirac theory with the energy gap. If the energy gaps for two valleys of the graphene hexagonal lattice are the same, the charge densities corresponding to the separate valleys cancel each other, whereas the azimuthal current is doubled.

show abstract

Vacuum fermionic currents in braneworld models on AdS bulk with a cosmic string

Bellucci

dos

Mello

et al. 2021

J. High Energ. Phys.

View full text Add to dashboard Cite

We investigate the effects of a brane and magnetic-flux-carrying cosmic string on the vacuum expectation value (VEV) of the current density for a charged fermionic field in the background geometry of (4+1)-dimensional anti-de Sitter (AdS) spacetime. The brane is parallel to the AdS boundary and the cosmic string is orthogonal to the brane. Two types of boundary conditions are considered on the brane that include the MIT bag boundary condition and the boundary conditions in Z2-symmetric braneworld models. The brane divides the space into two regions with different properties of the vacuum state. The only nonzero component of the current density is along the azimuthal direction and in both the regions the corresponding VEV is decomposed into the brane- free and brane-induced contributions. The latter vanishes on the string and near the string the total current is dominated by the brane-free part. At large distances from the string and in the region between the brane and AdS horizon the decay of the brane-induced current density, as a function of the proper distance, is power-law for both massless and massive fields. For a massive field this behavior is essentially different from that in the Minkowski bulk. In the region between the brane and AdS boundary the large-distance decay of the current density is exponential. Depending on the boundary condition on the brane, the brane-induced contribution is dominant or subdominant in the total current density at large distances from the string. By using the results for fields realizing two inequivalent irreducible representations of the Clifford algebra, the vacuum current density is investigated in C - and P -symmetric fermionic models. Applications are given for a cosmic string in the Randall-Sundrum-type braneworld model with a single brane.

show abstract

Fermionic current densities induced by magnetic flux in a conical space with a circular boundary

Cited by 66 publications

References 80 publications

Finite temperature fermionic charge and current densities induced by a cosmic string with magnetic flux

Finite temperature fermionic charge and current densities induced by a cosmic string with magnetic flux

Induced fermionic charge and current densities in two-dimensional rings

Vacuum fermionic currents in braneworld models on AdS bulk with a cosmic string

Contact Info

Product

Resources

About