Characterization of topological states on a lattice with Chern number

We study Chern numbers to characterize the ground state of strongly interacting systems on a lattice. This method allows us to perform a numerical characterization of bosonic fractional quantum Hall (FQH) states on a lattice where conventional overlap calculation with known continuum case such as Laughlin state, breaks down due to the lattice structure or dipole-dipole interaction. The non-vanishing Chern number indicates the existence of a topological order in the degenerate ground state manifold.Comment: 5 pages, 3 figures, V2: changes in the presentatio

Topologically Robust Transport of Photons in a Synthetic Gauge Field

Electronic transport in low dimensions through a disordered medium leads to localization. The addition of gauge fields to disordered media leads to fundamental changes in the transport properties. For example, chiral edge states can emerge in two-dimensional systems with a perpendicular magnetic field. Here, we implement a "synthetic'' gauge field for photons using silicon-on-insulator technology. By determining the distribution of transport properties, we confirm the localized transport in the bulk and the suppression of localization in edge states, using the "gold standard'' for localization studies. Our system provides a new platform to investigate transport properties in the presence of synthetic gauge fields, which is important both from the fundamental perspective of studying photonic transport and for applications in classical and quantum information processing.Comment: 4.5 pages, 3 figures and supplementary materia

Photonic quantum transport in a nonlinear optical fiber

We theoretically study the transmission of few-photon quantum fields through a strongly nonlinear optical medium. We develop a general approach to investigate nonequilibrium quantum transport of bosonic fields through a finite-size nonlinear medium and apply it to a recently demonstrated experimental system where cold atoms are loaded in a hollow-core optical fiber. We show that when the interaction between photons is effectively repulsive, the system acts as a single-photon switch. In the case of attractive interaction, the system can exhibit either antibunching or bunching, associated with the resonant excitation of bound states of photons by the input field. These effects can be observed by probing statistics of photons transmitted through the nonlinear fiber

Impact of creatinine clearance on helicobacter pylori eradication rate in patients with peptic ulcer disease

Introduction. Gastrointestinal complaints are common in patients with kidney failure. The aim of this study was to investigate the effect of creatinine clearance on Helicobacter pylori (HP) eradication rate in patients with peptic ulcer disease. Materials and Methods. In this clinical trial, 132 patients with a range of kidney function (normal to end-stage renal disease) and peptic ulcer disease with HP infection were enrolled and divided into 5 groups by their creatinine clearance. For all patients, a 14-day standard regimen of triple therapy for peptic ulcer was started with omeprazole, 20 mg; clarithromycin, 500 mg; and amoxicillin, 1 g; twice per day. After 6 weeks, HP eradication rate were evaluated and compared between the groups with urea breath test. Results. The mean age of the participants was 44.84 ± 12.20 years and 68 (51.5%) were women. The five groups were not significantly different in terms of age, sex distribution, or body mass index. The results of urea breath test at 6 weeks were positive in 23 patients (17.4%). There was no significant difference in HP eradication rate (negative urea breath test) between the five groups. Conclusions. This study showed no association between the success rate of eradication of HP infection and kidney function. © 2015, Iranian Society of Nephrology. All rights reserved

High-Order Multipole Radiation from Quantum Hall States in Dirac Materials

We investigate the optical response of strongly disordered quantum Hall states in two-dimensional Dirac materials and find qualitatively different effects in the radiation properties of the bulk versus the edge. We show that the far-field radiation from the edge is characterized by large multipole moments (> 50) due to the efficient transfer of angular momentum from the electrons into the scattered light. The maximum multipole transition moment is a direct measure of the coherence length of the edge states. Accessing these multipole transitions would provide new tools for optical spectroscopy and control of quantum Hall edge states. On the other hand, the far-field radiation from the bulk appears as random dipole emission with spectral properties that vary with the local disorder potential. We determine the conditions under which this bulk radiation can be used to image the disorder landscape. Such optical measurements can probe sub-micron length scales over large areas and provide complementary information to scanning probe techniques. Spatially resolving this bulk radiation would serve as a novel probe of the percolation transition near half-filling.Comment: v2: 8 pages, 4 figure