Interaction-Induced Strong Localization in Quantum Dots

We argue that Coulomb blockade phenomena are a useful probe of the cross-over to strong correlation in quantum dots. Through calculations at low density using variational and diffusion quantum Monte Carlo (up to r_s ~ 55), we find that the addition energy shows a clear progression from features associated with shell structure to those caused by commensurability of a Wigner crystal. This cross-over (which occurs near r_s ~ 20 for spin-polarized electrons) is, then, a signature of interaction-driven localization. As the addition energy is directly measurable in Coulomb blockade conductance experiments, this provides a direct probe of localization in the low density electron gas.Comment: 4 pages, published version, revised discussio

Blood Pressure and Age Are the Main Determinants of Aortic Stiffness

WOS: 000418303200017PubMed ID: 28982100

Predictors of adverse perinatal outcomes in intrahepatic cholestasis of pregnancy

Objectives: Our objective was to evaluate in our clinic the perinatal outcomes of patients diagnosed with ICP based on pre-treatment maternal serum bile acid levels, attempt to identify the risk group and review the literature in light of this information.  Material and methods: In total, 370 patients diagnosed with ICP were included in the study, divided into two groups based on the fasting total serum bile acid level before UDCA (Group 1: 10 ≥ 40 μmol/L, and Group 2: ≥ 40 μmol/L). The groups were examined for clinical characteristics and pregnancy outcomes.  Results: It was found that preterm delivery and neonatal intensive care need increased at a serum bile acid cut-off value of 34 μmol/L. Regardless of serum bile acid, significantly higher rates of meconium-stained amniotic fluid and foetal distress were observed in patients whose diagnoses were made before 34 weeks of gestation.  Conclusions: Foetal complications over 40 μmol/L of serum bile acid were significantly increased. However, slightly lower levels cut-off values (34 μmol/L) were obtained in terms of preterm birth and neonatal intensive care need. The incidence of meconium-stained amniotic fluid and foetal distress was higher in patients whose diagnosis were made before 34 weeks of gestation.

Edge channel confinement in a bilayer graphene nn-pp-nn quantum dot

We combine electrostatic and magnetic confinement to define a quantum dot in bilayer graphene. The employed geometry couples $n$-doped reservoirs to a $p$-doped dot. At magnetic field values around $B = 2~$T, Coulomb blockade is observed. This demonstrates that the coupling of the co-propagating modes at the $p$-$n$ interface is weak enough to form a tunnel barrier, facilitating transport of single charge carriers onto the dot. This result may be of use for quantum Hall interferometry experiments

Operator representation and logistic extension of elementary cellular automata

We redefine the transition function of elementary cellular automata (ECA) in terms of discrete operators. The operator representation provides a clear hint about the way systems behave both at the local and the global scale. We show that mirror and complementary symmetric rules are connected to each other via simple operator transformations. It is possible to decouple the representation into two pairs of operators which are used to construct a periodic table of ECA that maps all unique rules in such a way that rules having similar behavior are clustered together. Finally, the operator representation is used to implement a generalized logistic extension to ECA. Here a single tuning parameter scales the pace with which operators iterate the rules. We show that, as this parameter is tuned, many rules of ECA undergo multiple phase transitions between periodic, locally chaotic, chaotic and complex (Class 4) behavior

On the Ginzburg-Landau Analysis of the Upper Critical Field Hc2 in MgB2

Temperature dependence of the upper critical field Hc2 (T) for the superconducting magnesium diboride, MgB2, is studied in the vicinity of Tc by using a two-band Ginzburg-Landau (G-L) theory. The temperature dependence of Hc2 (T) near Tc exhibits a positive curvature. In addition, the calculated temperature dependence and its higher order derivatives are also shown to be in a good agreement with the experimental data. In analogy with the multi-band character of Eliashberg microscopic theory, the positive curvature of Hc2 (T) is described reasonably by solving the two-band of G-L theory.Comment: 14 pages, 2 figures, submitted to SUST November 200

Correlation Induced Inhomogeneity in Circular Quantum Dots

Properties of the "electron gas" - in which conduction electrons interact by means of Coulomb forces but ionic potentials are neglected - change dramatically depending on the balance between kinetic energy and Coulomb repulsion. The limits are well understood. For very weak interactions (high density), the system behaves as a Fermi liquid, with delocalized electrons. In contrast, in the strongly interacting limit (low density), the electrons localize and order into a Wigner crystal phase. The physics at intermediate densities, however, remains a subject of fundamental research. Here, we study the intermediate-density electron gas confined to a circular disc, where the degree of confinement can be tuned to control the density. Using accurate quantum Monte Carlo techniques, we show that the electron-electron correlation induced by an increase of the interaction first smoothly causes rings, and then angular modulation, without any signature of a sharp transition in this density range. This suggests that inhomogeneities in a confined system, which exist even without interactions, are significantly enhanced by correlations.Comment: final version, modified introduction and clarifications, 4 page

Helminth fauna of Lebanon lizard, Phoenicolacerta laevis (Gray, 1838), (Squamata: Lacertidae) from Southern Turkey

In the years 2010 and 2014, fifty-four samples of Phoenicolacerta laevis from eight localities in Adana (n=6) and Hatay (n=48) were collected and examined for helminth parasites. New host and locality records were recorded. As a results of present study, three species of Digenea, Sonsinotrema tacapense, Prosthodendrium chilostomum, Brachylaima sp. (metacercaria); two species of Cestoda, Oochoristica tuberculata and Mesocestoides sp. and four species of Nematoda, Skrjabinodon medinae, Spauligodon sp., Thubunaea sp. and a larva of the Ascaridiidae Ascarididae gen. sp. were reported for lizard samples. We document new host records for all of helminth species reported here. Sonsionotrema tacapense (Digenea), and Thubunaea sp. (Nematoda) are recorded for the first time from Turkey. There are, to our knowledge, no reports of helminths for P. laevis in Turkey and also from its range

Strong suppression of Coulomb corrections to the cross section of e+e- pair production in ultrarelativistic nuclear collisions

The Coulomb corrections to the cross section of $e^+e^-$ pair production in ultrarelativistic nuclear collisions are calculated in the next-to-leading approximation with respect to the parameter $L=\ln \gamma_A\gamma_B$ ($\gamma_{A,B}$ are the Lorentz factors of colliding nuclei). We found considerable reduction of the Coulomb corrections even for large $\gamma_A\gamma_B$ due to the suppression of the production of $e^+e^-$ pair with the total energy of the order of a few electron masses in the rest frame of one of the nuclei. Our result explains why the deviation from the Born result were not observed in the experiment at SPS.Comment: 4 pages, RevTe

Coulomb Effects on Electromagnetic Pair Production in Ultrarelativistic Heavy-Ion Collisions

We discuss the implications of the eikonal amplitude on the pair production probability in ultrarelativistic heavy-ion transits. In this context the Weizs\"acker-Williams method is shown to be exact in the ultrarelativistic limit, irrespective of the produced particles' mass. A new equivalent single-photon distribution is derived which correctly accounts for the Coulomb distortions. As an immediate application, consequences for unitarity violation in photo-dissociation processes in peripheral heavy-ion encounters are discussed.Comment: 13 pages, 4 .eps figure