212 research outputs found

    Ground-state properties of one-dimensional anyon gases

    Full text link
    We investigate the ground state of the one-dimensional interacting anyonic system based on the exact Bethe ansatz solution for arbitrary coupling constant (0≀c≀∞0\leq c\leq \infty) and statistics parameter (0≀Îș≀π0\leq \kappa \leq \pi). It is shown that the density of state in quasi-momentum kk space and the ground state energy are determined by the renormalized coupling constant câ€Čc'. The effect induced by the statistics parameter Îș\kappa exhibits in the momentum distribution in two aspects: Besides the effect of renormalized coupling, the anyonic statistics results in the nonsymmetric momentum distribution when the statistics parameter Îș\kappa deviates from 0 (Bose statistics) and π\pi (Fermi statistics) for any coupling constant cc. The momentum distribution evolves from a Bose distribution to a Fermi one as Îș\kappa varies from 0 to π\pi. The asymmetric momentum distribution comes from the contribution of the imaginary part of the non-diagonal element of reduced density matrix, which is an odd function of Îș\kappa. The peak at positive momentum will shift to negative momentum if Îș\kappa is negative.Comment: 6 pages, 5 figures, published version in Phys. Rev.

    Particle partitioning entanglement in itinerant many-particle systems

    Full text link
    For itinerant fermionic and bosonic systems, we study `particle entanglement', defined as the entanglement between two subsets of particles making up the system. We formulate the general structure of particle entanglement in many-fermion ground states, analogous to the `area law' for the more usually studied entanglement between spatial regions. Basic properties of particle entanglement are uncovered by considering relatively simple itinerant models.Comment: 4 pages, 4 figure

    SO2 oxidation in supercooled droplets in the presence of O2

    Get PDF
    Sulphur dioxide oxidation in supercooled monodisperse droplets at T4213 7C was studied in the presence of oxygen. The SO2 concentration was found to range from 0.08 to 7.1 ppmv and the contact time between gases and droplets was 210 s. The experimental results showed that sulphate concentration due to SO2 oxidation is independent of temperature, i.e. the increase of SO2 solubility in the liquid phase balances the rate constant decrease of the oxidation reaction. Following McKay’s kinetics (Atmos. Environ., 5 (1971) 7), we calculated the rate constant at T4213 7C and the activation energy. A comparison was made between experimental S(VI) oxidation concentrations due to oxygen and theoretical oxidation values due to O3, H2O2 and oxygen in the presence of catalyzers (Fe31, Mn21)

    Finite-size effects in roughness distribution scaling

    Full text link
    We study numerically finite-size corrections in scaling relations for roughness distributions of various interface growth models. The most common relation, which considers the average roughness asscalingfactor,isnotobeyedinthesteadystatesofagroupofballistic−likemodelsin2+1dimensions,evenwhenverylargesystemsizesareconsidered.Ontheotherhand,goodcollapseofthesamedataisobtainedwithascalingrelationthatinvolvestherootmeansquarefluctuationoftheroughness,whichcanbeexplainedbyfinite−sizeeffectsonsecondmomentsofthescalingfunctions.Wealsoobtaindatacollapsewithanalternativescalingrelationthataccountsfortheeffectoftheintrinsicwidth,whichisaconstantcorrectiontermpreviouslyproposedforthescalingof as scaling factor, is not obeyed in the steady states of a group of ballistic-like models in 2+1 dimensions, even when very large system sizes are considered. On the other hand, good collapse of the same data is obtained with a scaling relation that involves the root mean square fluctuation of the roughness, which can be explained by finite-size effects on second moments of the scaling functions. We also obtain data collapse with an alternative scaling relation that accounts for the effect of the intrinsic width, which is a constant correction term previously proposed for the scaling of . This illustrates how finite-size corrections can be obtained from roughness distributions scaling. However, we discard the usual interpretation that the intrinsic width is a consequence of high surface steps by analyzing data of restricted solid-on-solid models with various maximal height differences between neighboring columns. We also observe that large finite-size corrections in the roughness distributions are usually accompanied by huge corrections in height distributions and average local slopes, as well as in estimates of scaling exponents. The molecular-beam epitaxy model of Das Sarma and Tamborenea in 1+1 dimensions is a case example in which none of the proposed scaling relations works properly, while the other measured quantities do not converge to the expected asymptotic values. Thus, although roughness distributions are clearly better than other quantities to determine the universality class of a growing system, it is not the final solution for this task.Comment: 25 pages, including 9 figures and 1 tabl

    Correlation amplitude and entanglement entropy in random spin chains

    Get PDF
    Using strong-disorder renormalization group, numerical exact diagonalization, and quantum Monte Carlo methods, we revisit the random antiferromagnetic XXZ spin-1/2 chain focusing on the long-length and ground-state behavior of the average time-independent spin-spin correlation function C(l)=\upsilon l^{-\eta}. In addition to the well-known universal (disorder-independent) power-law exponent \eta=2, we find interesting universal features displayed by the prefactor \upsilon=\upsilon_o/3, if l is odd, and \upsilon=\upsilon_e/3, otherwise. Although \upsilon_o and \upsilon_e are nonuniversal (disorder dependent) and distinct in magnitude, the combination \upsilon_o + \upsilon_e = -1/4 is universal if C is computed along the symmetric (longitudinal) axis. The origin of the nonuniversalities of the prefactors is discussed in the renormalization-group framework where a solvable toy model is considered. Moreover, we relate the average correlation function with the average entanglement entropy, whose amplitude has been recently shown to be universal. The nonuniversalities of the prefactors are shown to contribute only to surface terms of the entropy. Finally, we discuss the experimental relevance of our results by computing the structure factor whose scaling properties, interestingly, depend on the correlation prefactors.Comment: v1: 16 pages, 15 figures; v2: 17 pages, improved discussions and statistics, references added, published versio

    Critical interfaces and duality in the Ashkin Teller model

    Full text link
    We report on the numerical measures on different spin interfaces and FK cluster boundaries in the Askhin-Teller (AT) model. For a general point on the AT critical line, we find that the fractal dimension of a generic spin cluster interface can take one of four different possible values. In particular we found spin interfaces whose fractal dimension is d_f=3/2 all along the critical line. Further, the fractal dimension of the boundaries of FK clusters were found to satisfy all along the AT critical line a duality relation with the fractal dimension of their outer boundaries. This result provides a clear numerical evidence that such duality, which is well known in the case of the O(n) model, exists in a extended CFT.Comment: 5 pages, 4 figure

    Entanglement entropy and multifractality at localization transitions

    Full text link
    The von Neumann entanglement entropy is a useful measure to characterize a quantum phase transition. We investigate the non-analyticity of this entropy at disorder-dominated quantum phase transitions in non-interacting electronic systems. At these critical points, the von Neumann entropy is determined by the single particle wave function intensity which exhibits complex scale invariant fluctuations. We find that the concept of multifractality is naturally suited for studying von Neumann entropy of the critical wave functions. Our numerical simulations of the three dimensional Anderson localization transition and the integer quantum Hall plateau transition show that the entanglement at these transitions is well described using multifractal analysis.Comment: v3, 5 pages, published versio
    • 

    corecore