2,510 research outputs found
Towards a quantum-mechanical model for multispecies exclusion statistics
It is shown how to construct many-particle quantum-mechanical spectra of
particles obeying multispecies exclusion statistics, both in one and in two
dimensions. These spectra are derived from the generalized exclusion principle
and yield the same thermodynamic quantities as deduced from Haldane's
multiplicity formula.Comment: 12 pages, REVTE
Non-abelian statistics of half-quantum vortices in p-wave superconductors
Excitation spectrum of a half-quantum vortex in a p-wave superconductor
contains a zero-energy Majorana fermion. This results in a degeneracy of the
ground state of the system of several vortices. From the properties of the
solutions to Bogoliubov-de-Gennes equations in the vortex core we derive the
non-abelian statistics of vortices identical to that for the Moore-Read
(Pfaffian) quantum Hall state.Comment: 5 pages, 3 figures, REVTeX, epsf. Reference adde
Quantum liquids of particles with generalized statistics
We propose a phenomenological approach to quantum liquids of particles
obeying generalized statistics of a fermionic type, in the spirit of the Landau
Fermi liquid theory. The approach is developed for fractional exclusion
statistics. We discuss both equilibrium (specific heat, compressibility, and
Pauli spin susceptibility) and nonequilibrium (current and thermal
conductivities, thermopower) properties. Low temperature quantities have the
same temperature dependences as for the Fermi liquid, with the coefficients
depending on the statistics parameter. The novel quantum liquids provide
explicit realization of systems with a non-Fermi liquid Lorentz ratio in two
and more dimensions. Consistency of the theory is verified by deriving the
compressibility and -sum rules.Comment: 14 pages, Revtex, no figures; typos correcte
Holographic Charge Density Waves
We discuss a gravity dual of a charge density wave consisting of a U(1) gauge
field and two scalar fields in the background of an AdS Schwarzschild black
hole together with an antisymmetric field (probe limit). Interactions drive the
system to a phase transition below a critical temperature. We numerically
compute the ground states characterized by modulated solutions for the gauge
potential corresponding to a dynamically generated unidirectional charge
density wave in the conformal field theory. Signatures of the holographic
density waves are retrieved by studying the dynamical response to an external
electric field. We find that this novel holographic state shares many common
features with the standard condensed matter version of charge density wave
systems.Comment: 5 pages, 2 figures; improved discussion, published versio
Exclusion Statistics of Quasiparticles in Condensed States of Composite Fermion Excitations
The exclusion statistics of quasiparticles is found at any level of the
hierarchy of condensed states of composite fermion excitations (for which
experimental indications have recently been found). The hierarchy of condensed
states of excitations in boson Jain states is introduced and the statistics of
quasiparticles is found. The quantum Hall states of charged -anyons
( -- the exclusion statistics parameter) can be described as
incompressible states of -anyons ( -- an even number).Comment: 4 page
Holons on a meandering stripe: quantum numbers
We attempt to access the regime of strong coupling between charge carriers
and transverse dynamics of an isolated conducting ``stripe'', such as those
found in cuprate superconductors. A stripe is modeled as a partially doped
domain wall in an antiferromagnet (AF), introduced in the context of two
different models: the t-J model with strong Ising anisotropy, and the Hubbard
model in the Hartree-Fock approximation. The domain walls with a given linear
charge density are supported artificially by boundary conditions. In both
models we find a regime of parameters where doped holes lose their spin and
become holons (charge Q=1, spin S_z=0), which can move along the stripe without
frustrating AF environment. One aspect in which the holons on the AF domain
wall differ from those in an ordinary one-dimensional electron gas is their
transverse degree of freedom: a mobile holon always resides on a transverse
kink (or antikink) of the domain wall. This gives rise to two holon flavors and
to a strong coupling between doped charges and transverse fluctuations of a
stripe.Comment: Minor revisions: references update
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