137 research outputs found
Fermi distribution of semicalssical non-eqilibrium Fermi states
When a classical device suddenly perturbs a degenerate Fermi gas a
semiclassical non-equilibrium Fermi state arises. Semiclassical Fermi states
are characterized by a Fermi energy or Fermi momentum that slowly depends on
space or/and time. We show that the Fermi distribution of a semiclassical Fermi
state has a universal nature. It is described by Airy functions regardless of
the details of the perturbation. In this letter we also give a general
discussion of coherent Fermi states
Quantum Hydrodynamics, Quantum Benjamin-Ono Equation, and Calogero Model
Collective field theory for Calogero model represents particles with
fractional statistics in terms of hydrodynamic modes -- density and velocity
fields. We show that the quantum hydrodynamics of this model can be written as
a single evolution equation on a real holomorphic Bose field -- quantum
integrable Benjamin-Ono equation. It renders tools of integrable systems to
studies of nonlinear dynamics of 1D quantum liquids.Comment: 5 pages, 1 figur
Kinks in the Kondo problem
We find the exact quasiparticle spectrum for the continuum Kondo problem of
species of electrons coupled to an impurity of spin . In this
description, the impurity becomes an immobile quasiparticle sitting on the
boundary. The particles are ``kinks'', which can be thought of as field
configurations interpolating between adjacent wells of a potential with
degenerate minima. For the overscreened case , the boundary has this kink
structure as well, which explains the non-integer number of boundary states
previously observed. Using simple arguments along with the consistency
requirements of an integrable theory, we find the exact elastic -matrix for
the quasiparticles scattering among themselves and off of the boundary. This
allows the calculation of the exact free energy, which agrees with the known
Bethe ansatz solution.Comment: 9 pages +1 figur
Integrable Structure of Interface Dynamics
We establish the equivalence of a 2D contour dynamics to the dispersionless
limit of the integrable Toda hierarchy constrained by a string equation.
Remarkably, the same hierarchy underlies 2D quantum gravity.Comment: 5 pages, no figures, submitted to Phys. Rev. Lett, typos correcte
Impact of Achieved Blood Pressure on Cardiovascular Outcomes in the Irbesartan Diabetic Nephropathy Trial
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Haldane-Gapped Spin Chains as Luttinger Liquids: Correlation Functions at Finite Field
We study the behavior of Heisenberg, antiferromagnetic, integer-spin chains
in the presence of a magnetic field exceeding the attendant spin gap. For
temperatures much smaller than the gap, the spin chains exhibit Luttinger
liquid behavior. We compute exactly both the corresponding Luttinger parameter
and the Fermi velocity as a function of magnetic field. This enables the
computation of a number of correlators from which we derive the spin
conductance, the expected form of the dynamic structure factor relevant to
inelastic neutron scattering experiments, and NMR relaxation rates. We also
comment upon the robustness of the magnetically induced gapless phase both to
finite temperature and finite couplings between neighbouring chains.Comment: 32 pages, 8 figures; published version includes additions discussing
the robustness of the magnetically induced gapless phase to ordering between
chains as well as the relationship between the spin-1 chains and spin-1/2
ladders in the presence of a magnetic fiel
The exact solution of the s-d exchange model with arbitrary impurity spin s: Kondo problem
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