E. A. Pamyatnykh

Low-temperature effects of resonance electronic states at transition-element impurities in the kinetic, magnetic, and acoustic properties of semiconductors

New research results on phenomena due to the existence of electronic resonance energy levels and hybridized states at impurities of transition elements in semiconductors are presented. The data show that the thermal conductivity and ultrasonic parameters of mercury selenide containing iron impurities have resonance anomalies due to the influence of these impurities. A consistent and detailed interpretation is offered for the set of observed effects of hybridized states in mercury selenide with iron impurities. The proposed interpretation of the data obtained on other systems is discussed.

Experimental observation of spontaneous spin polarization of electrons in hybridized states of transition element impurities in semiconductors

Experimental evidence of the possible existence of spontaneous spin polarization of the electron system in hybridized states formed by transition element impurity atoms in the conduction band of semiconducting crystals is examined. The details of a quantitative interpretation of experiments on the temperature dependence of the specific heat and elastic moduli of mercury selenide crystals with iron impurities confirm the feasibility of establishing the presence of electron spin polarization in this type of experiment, as well as the possible existence of polarization in the crystals studied here. Theoretical arguments support the observation of a thermodynamic anomalous Hall effect owing to spontaneously polarized donor electrons from low-concentration impurities.

Spontaneous spin polarization of systems with impurity hybridized electron states in conduction band of crystals

A theoretical description of spontaneous spin polarization in systems of hybridized electron states on donor impurities with low concentration in a conduction band of a crystal is developed. On the base of general equations for the energy of spin splitting of the electron spectrum, formulated within the framework of the Fermi-liquid approach, it is shown that in systems of such a type the spin ordering mechanism of conduction electrons, which is more efficient than the usually considered mechanism of an exchange interaction with magnetic impurities, takes place. The possible realization of spontaneous spin ordering of electrons in hybridized states is substantiated for the case of total polarization of the system within the model of Fermi-liquid constants. Possibilities of finding manifestations of spontaneous spin polarization of an electron impurity system in thermodynamic properties (heat capacity and elastic moduli) are discussed. Evidences of such manifestations are presented from an analysis of avai...

Determination of effective magnetic moments of the hybridized electronic states of impurities from the concentration dependence of the Curie constant

The concentration dependence of the Curie constant in the magnetic susceptibility of impurities of transition elements in a nonmagnetic matrix is considered for the case where the energy level of an impurity electron falls into the conduction band and hybridized states arise. As a result of an analysis of the new experimental data on the magnetic susceptibility of the iron impurity in crystals of mercury selenide, a substantiation of the earlier proposed simple formula that describes the linear dependence of the Curie constant on the concentration of impurities with allowance for the hybridization of states is given. The application of this formula to the description of the temperature dependence of the magnetic susceptibility of the cobalt impurities allowed us, on the basis of the formulated ideas about the arrangement of the energy levels of d electrons and of the available data on the Hall concentration of electrons, to find the effective spin of the hybridized electronic states at the impurity cobalt and the resonance value of the concentration of donor electrons.

On the theoretical description of low-temperature effects in metals and doped semiconductors on the basis of the quantum theory of an electron liquid

A formulation of the initial principles of the quantum theory of an electron liquid as a basis for a theoretical description of the contribution of weakly excited single-particle states of an electronic system to the low-temperature properties of solids is presented. The present quantum-mechanical formulation, which leaves the real single-particle basis initially unspecified, makes it possible to study the role of the interelectronic interaction in the presence of orbital quantization and in circumstances where other quantum phenomena play a large role. A brief description is given of the derivation of the basic thermodynamic relations and expressions are given for the specific heat, elastic moduli, and magnetic susceptibility, all obtained on the basis of the Fermi-liquid approach without the conventionally used model assumptions. The application of the theory presented here to the description of the role of the interelectronic interaction in thermodynamic phenomena in systems with hybridized electronic ...

Fermi-liquid anomaly of the concentration dependence of the g-factor of the conduction electrons in a semiconductor with hybridized impurity states

A theoretical description is given of the concentration dependence of the g factor of the conduction electrons in hybridized states on donor impurities in a semiconductor taking account of the effect of the interelectronic interaction within the framework of the Fermi-liquid approach. It is shown that the theoretically predicted dependence due to the Fermi-liquid interaction is non-monotonic in the resonance interval because of partial electron localization on impurities.

Thermodynamic anomalous Hall effect: The quantum regime

A quantum statistical description of the anomalous Hall effect is developed within the framework of the previously proposed thermodynamic mechanism of the anomalous Hall effect in weakly magnetic electron systems with spontaneous spin polarization. A qualitative explanation of the physical nature of the thermodynamic mechanism is followed by a general formulation of the quantum theory of the effect, based on accounting for the local-equilibrium currents. The behavior of the magnetic field dependences and quantum magnetic oscillations of the physical parameters characterizing the anomalous Hall effect is discussed.

Theory of acoustic magnetic resonance in the surface elastic waves absorption by metal multilayers

Abstract In view of the magnetoelastic interaction in a metal magnetic multilayer such as Fe/Cr the magnetoelastic contribution to the absorption of the surface elastic waves is calculated. This contribution is proportional to dynamic magnetic susceptibility χ and as a consequence its dependence on the magnetic field strength has a resonance character.

Acoustic magnetic resonance in absorption and dispersion of surface elastic waves in multilayers

It is shown that magnetic resonances related to excitation of oscillations of the layer magnetization can appear in the spectrum and absorption of the Love acoustic surface waves propagating in a multilayered film with a Fe/Cr type magnetic ordering on a massive substrate. The magnetoelastic resonant contribution to the elastic shear modulus of the film is calculated and the relation between the resonant frequencies and the frequencies of electromagnetically excited uniform ferromagnetic resonance is established.

Ultrasound absorption by electrons in metallic magnetic multilayers and its correlation with giant magnetoresistance

Abstract Effects of the same origin as the giant magnetoresistance can be observed in the absorption of long-wave ultrasound penetrating through metallic multilayers. The correlation between the magnetic field dependence of the absorption coefficient and the magnetoresistance is defined by a specific mechanism of the effect.