3,411 research outputs found
Thomas-Fermi Method For Particles Obeying Generalized Exclusion Statistics
We use the Thomas-Fermi method to examine the thermodynamics of particles
obeying Haldane exclusion statistics. Specifically, we study
Calogero-Sutherland particles placed in a given external potential in one
dimension. For the case of a simple harmonic potential (constant density of
states), we obtain the exact one-particle spatial density and a {\it closed}
form for the equation of state at finite temperature, which are both new
results. We then solve the problem of particles in a potential
(linear density of states) and show that Bose-Einstein condensation does not
occur for any statistics other than bosons.Comment: 10 pages (TeX), 2 figures available upon reques
Effective mass of composite fermion: a phenomenological fit in with anomalous propagation of surface acoustic wave
We calculate the conductivity associated with the anomalous propagation of a
surface acoustic wave above a two-dimensional electron gas at .
Murthy-Shankar's middle representation is adopted and a contribution to the
response functions beyond the random phase approximation has been taken into
account. We give a phenomenological fit for the effective mass of composite
fermion in with the experimental data of the anomalous propagation of surface
acoustic wave at and find the phenomenological value of the effective
mass is several times larger than the theoretical value
derived from the Hartree-Fock approximation. We
compare our phenomenologically fitting composite fermion effective mass with
those appeared in the measurements of the activation energy and the
Shubnikov-de Haas effect and find that our result is fairly reasonable.Comment: 8 pages, 5 figures, the longer version of cond-mat/9801131 with
crucial corrections, accepted for publication by PR
Novel correlations in two dimensions: Some exact solutions
We construct a new many-body Hamiltonian with two- and three-body
interactions in two space dimensions and obtain its exact many-body ground
state for an arbitrary number of particles. This ground state has a novel
pairwise correlation. A class of exact solutions for the excited states is also
found. These excited states display an energy spectrum similar to the
Calogero-Sutherland model in one dimension. The model reduces to an analog of
the well-known trigonometric Sutherland model when projected on to a circular
ring.Comment: 8 pages, REVTE
Evolution of Magnetism in Single-Crystal Honeycomb Iridates
We report the successful synthesis of single-crystals of the layered iridate,
(NaLi)IrO, , and a thorough study of
its structural, magnetic, thermal and transport properties. The new compound
allows a controlled interpolation between NaIrO and LiIrO,
while maintaing the novel quantum magnetism of the honeycomb Ir planes.
The measured phase diagram demonstrates a dramatic suppression of the N\'eel
temperature, , at intermediate suggesting that the magnetic order in
NaIrO and LiIrO are distinct, and that at , the
compound is close to a magnetically disordered phase that has been sought after
in NaIrO and LiIrO. By analyzing our magnetic data with a
simple theoretical model we also show that the trigonal splitting, on the
Ir ions changes sign from NaIrO and LiIrO, and the
honeycomb iridates are in the strong spin-orbit coupling regime, controlled by
\jeff=1/2 moments.Comment: updated version with more dat
ANALYTICAL APPLICATIONS OF SAFRANIN O
A simple and sensitive spectrophotometric method has been developed for the estimation of Mycophenolic acid. The method is based on the formation of  Ion-Association complex with MYCO formed an ion -association complex with basic dye, SafraninO. The cationic form of the dye SAFO involves in the formation of neutral coloured ion-association complexe with negative charge (acid groups in the drug) which is extractable into chloroform and behaves as a single unit being held together by electrostatic attraction. The absorption maxima were found to be at lMax 520 nm. The method obeys Beer's law within the limits 10-40µg/ml and gives reproducible results. Molar absorptivity value is obtained as8.424x104 L mol-1 cm-1 and recovery was found to be 99.17 ± 0.92 to 99.62 ± 0.27. Interferences of the other ingredients and excipients were not observed. The proposed method can be used for the determination of MYCO both in pure and pharmaceutical formulations. KeyWords: Mycophenolicacid (MYCO), SafraninO (SAFO), Ion- association Comple
Exactly solvable toy models of unconventional magnetic alloys: Bethe Ansatz versus Renormalization Group method
We propose toy models of unconventional magnetic alloys, in which the density
of band states, , and hybridization, , are energy
dependent; it is assumed, however, that
, and hence an effective
electron-impurity coupling is
energy independent. In the renormalization group approach, the physics of the
system is assumed to be governed by only rather than by
separate forms of and . However, an exact Bethe
Ansatz solution of the toy Anderson model demonstrates a crucial role of a form
of inverse band dispersion .Comment: A final version. A previous one has been sent to Archive because of
my technical mistake. Sorr
Hamiltonian Description of Composite Fermions: Aftermath
The Lowest Landau Level (LLL), long distance theory of Composite Fermions
(CF) developed by Murthy and myself is minimally extended to all distances,
guided by very general principles. The resulting theory is mathematically
consistent, and physically appealing: we clearly see the electron and the
vortices binding to form the CF. The meaning of the constraints, their role in
ensuring compressibility of dipolar objects at , and the
observability of dipoles are clarified.Comment: Revised for publication in PRL, 4 - epsilon page
Unified approach to photo and electro-production of mesons with arbitrary spins
A new approach to identify the independent amplitudes along with their
partial wave multipole expansions, for photo and electro-production is
suggested,which is generally applicable to mesons with arbitrary spin-parity.
These amplitudes facilitate direct identification of different resonance
contributions.Comment: 11 page
Solitons in one-dimensional interacting Bose-Einstein system
A modified Gross-Pitaevskii approximation was introduced recently for bosons
in dimension by Kolomeisky {\it et al.} (Phys. Rev. Lett. {\bf 85} 1146
(2000)). We use the density functional approach with sixth-degree interaction
energy term in the Bose field to reproduce the stationary-frame results of
Kolomeisky {\it et al.} for a one-dimensional Bose-Einstein system with a
repulsive interaction. We also find a soliton solution for an attractive
interaction, which may be boosted to a finite velocity by a Galilean
transformation. The stability of such a soliton is discussed analytically. We
provide a general treatment of stationary solutions in one dimension which
includes the above solutions as special cases. This treatment leads to a
variety of stationary wave solutions for both attractive and repulsive
interactions.Comment: Latex, 14 pages, No figur
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