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1.
Sci Rep ; 12(1): 7369, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513406

RESUMO

Spin waves in magnetic microresonators are at the core of modern magnonics. Here we demonstrate a new method of tunable excitation of different spin wave modes in magnetic microdisks by using a train of laser pulses coming at a repetition rate higher than the decay rate of spin precession. The microdisks are etched in a transparent bismuth iron garnet film and the light pulses influence the spins nonthermally through the inverse Faraday effect. The high repetition rate of the laser stimulus of 10 GHz establishes an interplay between the spin wave resonances in the frequency and momentum domains. As a result, scanning of the focused laser spot near the disk boarder changes interference pattern of the magnons and leads to a resonant dependence of the spin wave amplitude on the external magnetic field. Apart from that, we achieved a switching between volume and surface spin waves by a small variation of the external magnetic field.

2.
Sci Rep ; 7(1): 5668, 2017 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-28720815

RESUMO

Currently spin waves are considered for computation and data processing as an alternative to charge currents. Generation of spin waves by ultrashort laser pulses provides several important advances with respect to conventional approaches using microwaves. In particular, focused laser spot works as a point source for spin waves and allows for directional control of spin waves and switching between their different types. For further progress in this direction it is important to manipulate with the spectrum of the optically generated spin waves. Here we tackle this problem by launching spin waves by a sequence of femtosecond laser pulses with pulse interval much shorter than the relaxation time of the magnetization oscillations. This leads to the cumulative phenomenon and allows us to generate magnons in a specific narrow range of wavenumbers. The wavelength of spin waves can be tuned from 15 µm to hundreds of microns by sweeping the external magnetic field by only 10 Oe or by slight variation of the pulse repetition rate. Our findings expand the capabilities of the optical spin pump-probe technique and provide a new method for the spin wave generation and control.

3.
Probl Econ ; 32(1): 33-51, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-12315685

RESUMO

PIP: A methodological approach is developed to analyze the well-being of family households among the rural population of Altai Krai, USSR. Well-being is defined in both material and nonmaterial terms, and various factors are assigned components to construct an integral typology of families. Implications for the development of social policy to improve the socioeconomic status of poor families are discussed.^ieng


Assuntos
Características da Família , Família , Modelos Teóricos , Pobreza , Política Pública , Qualidade de Vida , Pesquisa , População Rural , Classe Social , Demografia , Países Desenvolvidos , Economia , População , Características da População , Seguridade Social , Fatores Socioeconômicos , U.R.S.S.
4.
Biull Eksp Biol Med ; 106(12): 732-4, 1988 Dec.
Artigo em Russo | MEDLINE | ID: mdl-3207883

RESUMO

The influence of the method of preservation and application of medicinal preparation xydiphone on the process of calcification of xenograft bioprostheses in a classic model of subcutaneous implantation of bioprosthesis cusps in rats has been studied. It is estimated that fermentative processing does not influence the intensity of calcification, while the immobilization of heparin to tissue decreases the amount of calcium in implants 4.5 times. Combination of heparin immobilization with peroral administration of xydiphone results in summing up of the effects, decreasing the amount of calcium in experimental set of cusps up to the level of nonimplanted ones.


Assuntos
Bioprótese/efeitos adversos , Calcinose/prevenção & controle , Doenças das Valvas Cardíacas/prevenção & controle , Próteses Valvulares Cardíacas/efeitos adversos , Animais , Valva Aórtica , Difosfonatos/uso terapêutico , Avaliação Pré-Clínica de Medicamentos , Ácido Etidrônico , Feminino , Heparina/uso terapêutico , Falha de Prótese , Ratos , Preservação de Tecido/métodos
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