32,917 research outputs found
Creation of macroscopic superpositions of flow states with Bose-Einstein condensates
We present a straightforward scheme for creating macroscopic superpositions
of different superfluid flow states of Bose-Einstein condensates trapped in
optical lattices. This scheme has the great advantage that all the techniques
required are achievable with current experiments. Furthermore, the relative
difficulty of creating cats scales favorably with the size of the cat. This
means that this scheme may be well-suited to creating superpositions involving
large numbers of particles. Such states may have interesting technological
applications such as making quantum-limited measurements of angular momentum.Comment: 9 pages, 7 figure
Acquired Elliptocytosis as a Manifestation of Myelodysplastic Syndrome with Ring Sideroblasts and Multilineage Dysplasia.
Acquired elliptocytosis is a known but rarely described abnormality in the myelodysplastic syndromes (MDS). Here we report the case of an elderly male who was admitted to the hospital with chest pain, dyspnea, and fatigue and was found to be anemic with an elliptocytosis that had only recently been noted on peripheral smears of his blood. After bone marrow biopsy he was diagnosed with MDS with ring sideroblasts and multilineage dysplasia and acquired elliptocytosis. Here we report a rare case of acquired elliptocytosis cooccurring with MDS with ring sideroblasts and multilineage dysplasia
From the ISR to RHIC--measurements of hard-scattering and jets using inclusive single particle production and 2-particle correlations
Hard scattering in p-p collisions, discovered at the CERN ISR in 1972 by the
method of leading particles, proved that the partons of Deeply Inelastic
Scattering strongly interacted with each other. Further ISR measurements
utilizing inclusive single or pairs of hadrons established that high pT
particles are produced from states with two roughly back-to-back jets which are
the result of scattering of constituents of the nucleons as desribed by Quantum
Chromodynamics (QCD), which was developed during the course of these
measurements. These techniques, which are the only practical method to study
hard-scattering and jet phenomena in Au+Au central collisions at RHIC energies,
are reviewed, as an introduction to present RHIC measurements.Comment: To appear in the proceedings of the workshop on Correlations and
Fluctuations in Relativistic Nuclear Collisions, MIT, Cambridge, MA, April
21-23, 2005, 10 pages, 9 figures, Journal of Physics: Conference Proceeding
Orbital eigenchannel analysis for ab-initio quantum transport calculations
We show how to extract the orbital contribution to the transport
eigenchannels from a first-principles quantum transport calculation in a
nanoscopic conductor. This is achieved by calculating and diagonalizing the
first-principles transmission matrix reduced to selected scattering
cross-sections. As an example, the orbital nature of the eigenchannels in the
case of Ni nanocontacts is explored, stressing the difficulties inherent to the
use of non-orthogonal basis sets and first-principles Hamiltonians.Comment: 5 pages, 5 figurs; replaced with final version, introduction revised;
to be published in PR
Analysis of the Kondo effect in ferromagnetic atomic-sized contacts
Atomic contacts made of ferromagnetic metals present zero-bias anomalies in
the differential conductance due to the Kondo effect. These systems provide a
unique opportunity to perform a statistical analysis of the Kondo parameters in
nanostructures since a large number of contacts can be easily fabricated using
break-junction techniques. The details of the atomic structure differ from one
contact to another so a large number of different configurations can be
statistically analyzed. Here we present such a statistical analysis of the
Kondo effect in atomic contacts made from the ferromagnetic transition metals
Ni, Co and Fe. Our analysis shows clear differences between materials that can
be understood by fundamental theoretical considerations. This combination of
experiments and theory allow us to extract information about the origin and
nature of the Kondo effect in these systems and to explore the influence of
geometry and valence in the Kondo screening of atomic-sized nanostructures.Comment: 17 pages, 11 figure
Exact factorization of correlation functions in 2-D critical percolation
By use of conformal field theory, we discover several exact factorizations of
higher-order density correlation functions in critical two-dimensional
percolation. Our formulas are valid in the upper half-plane, or any conformally
equivalent region. We find excellent agreement of our results with
high-precision computer simulations. There are indications that our formulas
hold more generally.Comment: 6 pages, 3 figures. Oral presentation given at STATPHYS 23. V2: Minor
additions and corrections, figures improve
- …