相关论文: Giant Microwave Absorption in Metallic Grains: Rel…
Abstract We study the temperature dependence of the absorption of microwaves by random-anisotropy magnets. It is governed by strong metastability due to the broad distribution of energy barriers separating different spin configurations. At…
Magnetic order and microwave absorption in amorphous ferromagnets and materials sintered from nanoscale ferromagnetic grains are investigated analytically and numerically within the random-anisotropy model. We show that a scaling argument…
Enhanced microwave absorption, larger than that in the normal state, is observed in fine grains of type-II superconductors (MgB$_2$ and K$_3$C$_{60}$) for magnetic fields as small as a few $\%$ of the upper critical field. The effect is…
Microscopic model of the interaction of spins with a microwave field in a random-anisotropy magnet has been developed. Numerical results show that microwave absorption occurs in a broad range of frequencies due to the distribution of…
We have performed simultaneous measurements of microwave absorption/reflection and magneto-transport characteristics of a high mobility two-dimensional electrons in GaAs/AlGaAs heterostructure in regime of Microwave-Induced Resistance…
We study magnetic-field-dependent nonresonant microwave absorption and dispersion in thin La$_{0.7}$Sr$_{0.3}$MnO$_{3}$ films and show that it originates from the colossal magnetoresistance. We develop the model for magnetoresistance of a…
In this article we study microwave absorption in superconductors in the presence of a vortex lattice. We show that in addition to the conventional absorption mechanism associated with the vortex core motion, there is another mechanism of…
This paper gives a short summary of a mechanism of the enhanced paramagnetic relaxation that acts on rapidly rotating interstellar grains. We show that the Barnett magnetization that arises from grain rotation ensures that paramagnetic…
Why does a microwave oven work? How does biological tissue absorb electromagnetic radiation? Astonishingly, we do not have a definite answer to these simple questions because the microscopic processes governing the absorption of…
We report microwave magnetoabsorption (P) at room temperature in R0.6Sr0.4MnO3 (R = Pr and Nd) samples. P as a function of dc magnetic field (-2.5 kOe to +2.5 kOe) was measured for a broad frequency range (f = 0.1 - 4 GHz) of microwave…
We have performed magnetoresistance (MR) measurements of granular ferromagnets having lateral dimensions smaller than 0.5 $\mu$m and containing a small number of grains (down to about 100). Compared to macroscopic samples, these granular…
We model s- and d-wave ceramic superconductors with a three-dimensional lattice of randomly distributed Josephson junctions with finite self-inductance. The field and temperature dependences of the microwave absoption are obtained by…
The experimental investigation of a broadband far-infrared meta-material absorber is described. The observed absorptance is $>\,0.95$ from ${\rm 1-20\,THz}$ (${\rm 300-15\,\mu m}$) over a temperature range spanning ${\rm 5-300\,K}$. The…
We discuss the applied magnetic field dependence of the absorption of microwaves by a 3-dimensional array up to 30x30x30 Josephson junctions with random parameters including the resistivity, capacity and inductance of each junction. The…
The optical properties of small spherical iron grains are derived using a Kramers-Kronig-consistent model of the dielectric function including its dependence on temperature and size. Especially discussed is the effect of the size…
Magnetic refrigeration (MR) based on the magnetocaloric effect (MCE) is a promising alternative to conventional vapor compression refrigeration techniques. The cooling efficiency of a magnetic refrigerator depends on its refrigeration…
This work reports experimental evidence of random magnetic behavior observed in modified barium hexagonal ferrites. We observe a significant transition in the magnetic properties of this system when divalent cations (Ni2+, Cu2+, Mn2+) are…
For polycrystalline specimens of zeolites treated to thermal oxidation we have revealed and studied the weak spectra of reproducible magnetic microwave absorption fluctuations at a frequency of 9.4 GHz. The investigation was carried out by…
We discuss a novel physical mechanism which gives rise to a giant magnetoconductivity in non-centrosymmetric superconducting films. This mechanism is caused by a combination of spin-orbit interaction and inversion symmetry breaking in the…
We show that a common feature of temperature-dependent microwave absorption is the presence of absorption peaks. $ac$ loss peaks can arise when the internal $T$-dependent magnetic relaxation time crosses the measurement frequency. These…