We study XY and dimerized XX spin-1/2 chains with random exchange couplings by analytical and numerical methods and scaling considerations. We extend previous investigations to dynamical properties, to surface quantities, and operator profiles, and give a detailed analysis of the Griffiths phase. We present a phenomenological scaling theory of average quantities based on the scaling properties ...

In this paper we analyze integrable systems from a Clifford algebra point of view. This approach allows us to give a clear representation theoretic exposition of techniques used in spin systems, thereby showing their naturality. We then extend this approach to the analysis of the XX-model with nondiagonal boundaries which is among others related to growing and fluctuating interfaces and stochas...

We study the entropy of entanglement of the ground state in a wide family of one-dimensional quantum spin chains whose interaction is of finite range and translation invariant. Such systems can be thought of as generalizations of the XY model. The chain is divided in two parts: one containing the first consecutive L spins; the second the remaining ones. In this setting the entropy of entangleme...

We diagonalize the XX model with a finite number of spins and periodic boundary conditions. We solve for the ground state, focus on the rapidity of the convergence to the thermodynamic limit and study the features of multipartite entanglement.

Abstract By the hydrodynamic linear response theory, dynamical correlation functions decay as power laws along certain velocities, determined by flux Jacobian. Such correlations are obtained projections, and physically, they due to propagating ‘sound waves’ or generalisation thereof, transporting conserved quantities between observables. However, some observables do not emit sound waves, such o...

Recently there has been much interest in the study of finite one-dimensional quantum spin chains following the discovery of fractional S = —, ' spin states localized at the ends of S = 1 spin chains. ' In a recent paper, we showed numerically that the S = —, ' spin states can be understood within the framework of the Schwinger-boson mean-field theory (SBMFT) for the Heisenberg model. ' In this ...

We study the entanglement properties of anisotropic open spin one-half Heisenberg chains with a modified central bond. The entanglement entropy between the two half-chains is calculated with the density-matrix renormalization method (DMRG). We find a logarithmic behaviour with an effective central charge c′ varying with the length of the system. It flows to one in the ferromagnetic region and t...

The generalized Gibbs ensemble introduced for describing few-body correlations in exactly solvable systems following a quantum quench is related to the nonergodic way in which operators sample, in the limit of infinite time after the quench, the quantum correlations present in the initial state. The nonergodicity of the correlations is thus shown analyticallyto imply the equivalence with the ge...

Exact results for the dynamic dimer and trimer structure factors of the one-dimensional s = 1 2 XX model in a transverse magnetic field (‖ z) are presented and discussed in relation to known exact results for the dynamic spin structure factors. In the framework of the Jordan-Wigner representation, the accessible spectrum of the dimer fluctuation operator is limited to two-fermion excitations wh...

The 46,XX testicular disorder of sex development (DSD), also known as 46,XX male syndrome, is a rare form of DSD and clinical phenotype shows complete sex reversal from female to male. The sex-determining region Y (SRY) gene can be identified in most 46,XX testicular DSD patients; however, approximately 20% of patients with 46,XX testicular DSD are SRY-negative. The SRY-box 9 (SOX9) gene has se...