Upon cooling, the isolated ferromagnetic domains in thin films of La0.33Pr0.34Ca0.33MnO3 start to grow and merge at the metal-insulator transition temperature TP1, leading to a steep drop in resistivity, and continue to grow far below TP1. In contrast, upon warming, the ferromagnetic domain size remains unchanged until near the transition temperature. The jump in the resistivity results from th...

polymer-graphite powder composite behaves as a low-conductive material which can be used as an automatic fuse for adhesive connector in electrical circuits. the conductivity of this composite, below its transition temperature, tt, depends on concentration of carbon powder, slowly decreases as the temperature increases. meanwhile, the electrical resistivity of this material in transition tempera...

We consider the role of potential scatterers in the nematic phase of Fe-based superconductors above the transition temperature to the (π, 0) magnetic state but below the orthorhombic structural transition. The anisotropic spin fluctuations in this region can be frozen by disorder, to create elongated magnetic droplets whose anisotropy grows as the magnetic transition is approached. Such states ...

We discuss the relation between the deconfining phase transition in gauge theories and the realization of the magnetic Z N symmetry. At low temperature the Z N symmetry is spontaneously broken while above the phase transition it is restored. This is intimately related to the change of behaviour of the spatial 't Hooft loop discussed in [1]. We also point out that the realization of the magnetic...

Spin reorientation is a magnetic phase transition in which rotation of the magnetization vector with respect to the crystallographic axes occurs upon a change in the temperature or magnetic field. For example, SmFeO3 shows a magnetization rotation from the c axis above 480 K to the a axis below 450 K, known as the Γ4 → Γ2 transition. This work reports the successful synthesis of the new single-...

We study the critical properties in cubic systems of antiferromagnetically coupled spin dimers near magnetic-field-induced quantum phase transitions. The quantum critical points in the zero-temperature phase diagram are determined from quantum Monte Carlo simulations. Furthermore, scaling properties of the uniform magnetization and the staggered transverse magnetization across the quantum phase...

The gigantic reduction of the electric resistivity under the applied magnetic field, CMR effect, is now widely accepted to appear in the vicinity of the insulator to metal transition of the perovskite manganites. Recently, we have discovered the first order transition from ferromagnetic metal to insulator in La0.88Sr0.12MnO3 of the CMR manganite. This phase transition induces the tremendous inc...

A recent study of non-extensive phase transitions in nuclei and nuclear clusters needs a probability model compatible with the appropriate Hamiltonian. For magnetic molecules a representation of the evolution by a Markov process achieves the required probability model that is used to study the probability density function (PDF) of the order parameter, i.e., the magnetization. The existence of o...

The mass spectrum of the 3d 3-state Potts model is considered in the broken phase (a) near the second order Ising critical point in the temperature-magnetic field plane and (b) near the weakly first order transition point at zero magnetic field. In the case (a), the mass spectrum is compared with the prediction from universality of mass ratios in the 3d Ising class; in the case (b) a mass ratio...

A systematic study of spin-dependent Mn K-edge x-ray absorption spectra was performed on La12xCaxMnO3 . By examining the changes in the pre-edge spectra with the temperature, a model of the excitation process is developed and used to predict the temperature dependent changes in the local magnetic ordering about Mn sites. The approach is of general applicability to perovskite systems. It can be ...