We analyze an anisotropic spin 1/2 two legs ladder in the presence of various type of random perturbations. The generic phase diagram for the pure system, in a way similar to spin one chains, consists of four phases: an Antiferromagnet, a Haldane gap or a Singlet phase (depending on the sign of interchain coupling) and two XY phases designated by XY1 and XY2. The effects of disorder depend cruc...

XY-pic is a package for typesetting graphs and diagrams using Knuth’s TEX typesetting system. XY-pic works with most of the many formats available; e.g., plain TEX, LTEX, and AMS-TEX. Several styles of input for various diagram types are supported; they all share a mnemonic notation based on the logical composition of visual components. This guide concentrates on how to typeset “matrix-like” di...

The key role of the orbital degree of freedom to understanding the magnetic properties of layered ruthenates is discussed based on the 3-orbital Hubbard model coupled to lattice distortions, using numerical and mean-field techniques. In the G-type antiferromagnetic phase of Ca(2)RuO(4), recent x-ray experiments reported 0.5 holes/site in the d(xy) orbital, while d(yz) and d(zx) orbitals contain...

The magnetic-field-dependent ordering temperature of the quasi-2D quantum Heisenberg antiferromagnet (QHAF) Cu(pz)2(ClO4)2 was determined by calorimetric measurement in applied dc fields up to 33 tesla. The magnetic phase diagram shows a round maximum at 5.95 K and 17.5 T (at ≈ 1/3 of its saturation field), a 40 percent enhancement of the ordering temperature above the zero field value of 4.25 ...

Neutron scattering measurements show the ferromagnetic XY pyrochlore Yb2Ti2O7 to display strong quasi-two-dimensional (2D) spin correlations at low temperature, which give way to long range order (LRO) under the application of modest magnetic fields. Rods of scattering along 111 directions due to these 2D spin correlations imply a magnetic decomposition of the cubic pyrochlore system into decou...

This curve has the points (1 : 0 : 0) and (0 : 1 : 0) at infinity over any field. The affine equation is XY +Y +X = 0. The origin is a point of this curve. If (x, y) ∈ F8 is a point of this curve with nonzero coordinates, then x = 1. So 0 = xy + y + x = xy + xy + x = x[(xy) + (xy) + 1]. Let t = xy. Then t + t+ 1 = 0. So the Klein quartic has 3.7 = 21 rational points over F8 with nonzero coordin...

In this work, we investigate the evolution and settling of magnon condensation in spin-1/2 dimer system ${\mathrm{Sr}}_{3}{\mathrm{Cr}}_{2}{\mathrm{O}}_{8}$ using a combination magnetostriction pulsed fields inelastic neutron scattering continuous magnetic field. The structure Bose-Einstein phase was probed by diffraction up to 39 T. confirmed be an $\mathit{XY}$-antiferromagnetic validated irr...

The magnetotransport in single layer graphene has been experimentally investigated in magnetic fields up to 18 T as a function of temperature. A pronounced T dependence is observed for T≲50  K, which is either metallic, or insulating, depending on the filling factor ν. The metal-insulator transition (MIT) occurs at |ν{c}|∼0.65 and in the regime of the dissipative transport, where the longitudin...

The three-dimensional XY model is investigated in the presence of a uniform magnetic field applied $X$-direction. nearest neighbour intraplanar interaction considered ferromagnetic, and interplanar chosen to be antiferromagnetic. Starting from high-temperature initial random spin configuration, equilibrium phase system at any finite temperature was achieved by cooling using Monte Carlo single s...

Five and six dimensional SUSY gauge theories, with one or two compactified directions, are discussed. The 5d theories with the matter hypermultiplets in the fundamental representation are associated with the twisted XXZ spin chain, while the group product case with the bi-fundamental matter corresponds to the higher rank spin chains. The Riemann surfaces for 6d theories with fundamental matter ...