A generic lattice model for systems containing particles interacting with short-range attraction long-range repulsion (SALR) potential that can be solved exactly in one dimension is introduced. We assume attraction J1 between the first neighbors and repulsion J2 between the third neighbors. The ground state of the model shows existence of two homogeneous phases (gas and liquid) for J2/J1 <1/3. ...

We restudy the phase diagram of the 2D-Ising model with competing interactions J1 on nearest neighbour and J2 on next-nearest neighbour bonds via Monte-Carlo simulations. We present the finite temperature phase diagram and introduce computational methods which allow us to calculate transition temperatures close to the critical point at J2 = 0.5J1. Further on we investigate the character of the ...

NMR, μSR, magnetization and specific heat measurements in Li2VOSiO4 powders and single crystals are reported. Specific heat and magnetization measurements evidence that Li2VOSiO4 is a frustrated two-dimensional S = 1/2 Heisenberg antiferromagnet on a square lattice with a superexchange coupling J1, along the sides of the square, almost equal to J2, the one along the diagonal (J2/J1 = 1.1 ± 0.1 ...

The Lie algebra of the group SU2 is constructed from two deformed oscillator algebras for which the deformation parameter is a root of unity. This leads to an unusual quantization scheme, the {J2, Ur} scheme, an alternative to the familiar {J2, Jz} quantization scheme corresponding to common eigenvectors of the Casimir operator J and the Cartan operator Jz. A connection is established between t...

Imaging the magnetic fields around a non-magnetic impurity can provide a clear benchmark for quantifying the degree of magnetic frustration. Focusing on the strongly frustrated J1-J2 model and the spatially anisotropic J1a-J1b-J2 model, very distinct low energy behaviors reflect different levels of magnetic frustration. In the J1-J2 model, bound magnons appear trapped near the impurity in the g...

Winter survival dynamics of Meloidogyne incognita and M. arenaria were studied at nine sites in Texas for 2 years. Population survival from October until April was variable among sites, ranging from 0.1% to 33%. A negative correlation (r = -0.86, P = 0.01) was observed between initial population, densities in October and survival percentage until the following April. Total population (eggs + J2...

Critical and in the highly frustrated regime also dynamical properties of J1?J2 Ising model with competing nearest-neighbor J1 second-nearest-neighbor J2 interactions on a honeycomb lattice are investigated by standard Monte Carlo parallel tempering simulations. The phase boundary is determined as function coupling ratio for transition between paramagnetic ferromagnetic states within R?J2/|J1|?...

Motivated by the unabating interest in the spin-1/2 Heisenberg antiferromagnetic model on the kagome lattice, we investigate the energetics of projected Schwinger-boson (SB) wave functions in the J1-J2 model with antiferromagnetic J2 coupling. Our variational Monte Carlo results show that Sachdev’s Q1 = Q2 SB ansatz has a lower energy than the Dirac spin liquid for J2 0.08J1 and the q = 0 Jastr...

The aim of this paper is to dynamically constrain the quadrupole mass moment J2 of the main-sequence HD 209458 star. The adopted method is the confrontation between the measured orbital period of its transiting planet Osiris and a model of it. Osiris is assumed to move along an equatorial and circular orbit. Our estimate, for given values of the stellar massM and radiusR and by assuming the val...

Motivated by various spin-1/2 compounds like Cs2CuCl4 or κ-(BEDTTTF)2Cu2(CN)3, we derive a Raman-scattering operator à la Shastry and Shraiman for various geometries. For T=0, the exact spectra is computed by Lanczos algorithm for finite-size clusters. We perform a systematic investigation as a function of J2/J1, the exchange constant ratio: ranging from J2 = 0, the well known square-lattice ca...