Magnetic properties of DyCo2 and HoCo2 have been investigated in both low and high magnetic fields up to 350 T. At low temperature, the compounds form ferrimagnetic structure with the rare-earth moments close to 10 mu(B) and a Co moment of similar to 1 mu(B). With increasing temperature, the magnetic disordering occurs through the first-order type transition, which confirms the itinerant nature of magnetism of d-electron subsystem of Co. From the field dependences of the voltage induced in the measuring coils of the explosive magnetocumulative generator, the values of critical field of metamagnetic transition in the Co sublattice from a field-disordered to a magnetically ordered state were determined to be 295 T and 329 T for HoCo2 and DyCo2, respectively. Using reliable literature data on the field of metamagnetic transition for the exchange-enhanced Pauli paramagnet YCo2, the values of molecular fields of the intersublattice exchange interaction and R-Co exchange coupling parameter were directly estimated. The obtained data are compared with those determined previously by indirect methods.

Experiments on the dynamic isentropic compression of solid CO2 samples by the megabar pressure induced by the superstrong magnetic field of an explosive magnetic generator have been performed with the X-ray diffraction detection of the state of the compressed samples. The generator operation is based on the fast compression of the initial magnetic flux in the cavity of the generator by a conducting cylindrical liner accelerated by the products of the explosion of a cylindrical explosive charge. Two points at pressures of 349 and 459 GPa on the compressibility diagram of CO2 have been determined in the experiments, where the degree of compression ρ/ρ0 of CO2 has reached currently highest values of 3.90 and 4.02, respectively. Comparison has shown that theoretically calculated equations of states for crystal phases of CO2 almost completely reproduce the experimental results, which confirms a high accuracy of theoretical predictions and the identity of the experimental and theoretical equations of states of CO2 modifications stable at high pressures.

We demonstrate the peculiarities of the magnetization process in the ferrimagnetic intermetallic compound (Nd0.5Dy0.5)2Fe14B, which has been studied theoretically and experimentally using ultrahigh magnetic fields. We observe phase transition induced by external ultrahigh magnetic fields (up to 170 T) and also describe the magnetization process analytically in terms of critical transition fields. In this work, the first and second critical fields of the field-induced magnetic transitions, Hc1 and Hc2, were estimated, and the results were verified against experimental data for Hc1. Critical field Hc2 predicting the place of transition to the forced-ferromagnetic state was estimated for the first time for (Nd0.5Dy0.5)2Fe14B compound. A comparison of the magnetization behavior for (Nd0.5Dy0.5)2Fe14B with the basic systems Nd2Fe14B and Dy2Fe14B is also performed. We demonstrate that, in the Dy2Fe14B compound, the field-induced transition type is changed from the first to the second order due to the replacement of the Nd atom by Dy one.

A two-sublattice ferrimagnet undergoes a transition from a collinear to the canted magnetic phase at magnetic field oriented along an easy magnetization direction. In this work, we study the transition by means of the magneto-optical Faraday effect in a thin film of compensated iron garnet (Lu3−xBix)(Fe5−y−zGayAlz)O12 grown on the Gd3Ga5O12 substrate. In the immediate vicinity of the compensation temperature, a precursor of the transition with a complex shape was observed. Using a special sample with variable thickness, we demonstrate an interfacial origin of the precursor. Diffusion of gadolinium from the substrate into the film forms a thin intermixed layer with enhanced magnetization. It induces an extended inhomogeneous magnetic structure in the film. A two-step shape of the precursor appears due to an easy-plane anisotropy of the intermixed magnetic layer. We emphasize that an effective width of the inhomogeneous magnetization distribution in the film grows enormously while approaching the compensation temperature.

The results of the numerical simulation and experimental study of an entirely piezoceramic cylindrical resonator to generate sonoluminescence are presented. The data on the origin and study of single- and multibubble sonoluminescence in a water–air system are presented. It is shown that in a piezoelectric resonator sonoluminescence occurs under electric voltages, whose values of are one order of magnitude less than in resonators of other types.

The method of nonlocal trial variation function for quantum one-dimensional systems is developed on an example of a spin-1/2 XXZ chain with an alternating magnetic field. A four-site trial wave function for a fermionic representation of the model is constructed. The results obtained using the model with the extended trial wave function show a considerable improvement of accuracy of the ground state energy calculation in the field of critical behavior in comparison with the solutions obtained earlier. The methods for calculating the experimentally observed spin correlation function are considered.

A variational method with nonlocal trial function is developed for quantum one-dimensional systems. It is applied to the XXZ spin-1/2 chain with an alternating magnetic field. A four-node trial wave function for the fermionic representation of the model is constructed. The results obtained in the model with an extended trial wave function demonstrate a significant increase in the accuracy of the ground state energy in the region of critical behavior compared with the solutions obtained previously. A method for calculation of the spin correlation function are discussed.

Recently, an investigation of the Faraday rotation in thin iron garnet film (LuBi)(3)(FeAlGa)(5)O-12 revealed an unusual "precursor" of transition to a noncollinear phase. It was observed in the vicinity of the compensation temperature. However, this feature cannot be ascribed to the uniform phase transition associated with uniaxial anisotropy. A model for the "precursor" based on inhomogeneous magnetic structure at the substrate-film interface is presented. To interpret the Faraday rotation, two diamagnetic optical transitions attributed to tetrahedral and octahedral iron sublattices are considered.

The report presents a model of the magnetic structure of diluted iron garnets with nonmagnetic ions in a dodecahedral sublattice. The dilution of magnetic iron sublattices is assumed to be selective: in the limiting case, the substitution of nonmagnetic ions for iron takes place only in a tetrahedral sublattice. In this case, iron ions in the octahedral environment have a variable number of the nearest magnetic neighbors; thus, octahedral sublattice are introduced in the dependence on the number of magnetic neighbors. This model is shown to describe well the magnetic properties of diluted iron garnets with a compensation point.

A dynamic deformation of sheet magnetic and nonmagnetic metal workpieces under a combination of a slowly varying primary magnetic field and a sequence of short magnetic field pulses with the opposite polarity is studied. This regime corresponds to backward electromagnetic forming. A fast motion of the workpiece induces an additional electromotive force in a discharge circuit and substantially alters a shape of the current pulse in an inductor. During the short opposite pulses, the Lorentz and magnetization components of the magnetic pressure on the magnetic workpiece demonstrate an unusual behavior, that is, the Lorentz pressure is attractive and the magnetization one is predominantly repulsive relative to the inductor. This phenomenon is discussed in terms of a two-dimensional axisymmetric problem.

A model of the magnetic structure of diluted iron garnets with non-magnetic ions in the dodecahedral sublattice is presented. Dilution of magnetic iron sublattices is assumed to be selective: in the limiting case, the replacement of iron with non-magnetic ions occurs only in the tetrahedral sublattice. Then iron ions in the octahedral environment have a variable number of nearest magnetic neighbors, that is why, octahedral sublattices are introduced depending on the number of magnetic neighbors. It is shown that this model well describes the magnetic properties of dilute ferrite garnets with compensation point.

Abstract —A technique of measuring the rotation of the light polarization plane in pulsed magnetic fields with strength up to 40 T with a sensitivity of 0.1° is proposed. The Faraday effect has been studied in films of diluted ferrites—garnets (Lu,Bi)_3(Fe,Ga,Al)_5O_12 in the temperature range from room temperature to 78 K, including the vicinity of the magnetic moment compensation temperature. The transition to the noncollinear phase in the magnetic phase diagram is shown to occur at a magnetic field strength higher than 30 T at room temperature, and the threshold transition field tends to zero when approaching the magnetic moment compensation temperature.

Abstract—A technique of measuring the rotation of the light polarization plane in pulsed magnetic fields with strength up to 40 T with a sensitivity of  0.1° is proposed. The Faraday effect has been studied in films of diluted ferrites—garnets (Lu,Bi)3(Fe,Ga,Al)5O12 in the temperature range from room temperature to 78 K, including the vicinity of the magnetic moment compensation temperature. The transition to the noncollinear phase in the magnetic phase diagram is shown to occur at a magnetic field strength higher than 30 T at room temperature, and the threshold transition field tends to zero when approaching the magnetic moment compensation temperature.

A new variational technique for investigation of the ground state and correlation functions in 1D quantum magnets is proposed. A spin Hamiltonian is reduced to a fermionic representation by the Jordan–Wigner transformation. The ground state is described by a new non-local trial wave function, and the total energy is calculated in an analytic form as a function of two variational parameters. This approach is demonstrated with an example of the XXZ-chain of spin-1/2 under a staggered magnetic field. Generalizations and applications of the variational technique for low-dimensional magnetic systems are discussed.