Počet záznamů: 1

Terahertz and infrared studies of antiferroelectric phase transition in multiferroic Bi.sub.0.85./sub.Nd.sub.0.15./sub.FeO.sub.3./sub..

  1. 1.
    0367281 - FZU-D 2012 RIV US eng J - Článek v odborném periodiku
    Goian, Veronica - Kamba, Stanislav - Greicius, S. - Nuzhnyy, Dmitry - Karimi, S. - Reaney, I. M.
    Terahertz and infrared studies of antiferroelectric phase transition in multiferroic Bi0.85Nd0.15FeO3.
    Journal of Applied Physics. Roč. 110, č. 7 (2011), 074112/1-074112/5 ISSN 0021-8979
    Grant CEP: GA ČR GD202/09/H041; GA ČR(CZ) GA202/09/0682
    Grant ostatní:GA UK(CZ) SVV-2011-263303
    Výzkumný záměr: CEZ:AV0Z10100520
    Klíčová slova: multiferroics * infrared and THz spectroscopy * phonons * antiferroelectrics
    Kód oboru RIV: BM - Fyzika pevných látek a magnetismus
    Impakt faktor: 2.168, rok: 2011

    High-frequency dielectric studies of Bi0.85Nd0.15FeO3 ceramics performed betweeen 100 and 900 K reveal hardening of most polar phonons on cooling below antiferroelectric phase transition, which occurs near 600 K. Moreover, a strong THz dielectric relaxation is seen in paraelectric phase. Its relaxation frequency softens on cooling towards TC = 600 K, its dielectric strength simultaneously decreases, and finally the relaxation disappears from the spectra below 450 K. Both phonon and dielectric relaxation behavior are responsible for a decrease in the dielectric permittivity at the antiferroelectric phase transition. Origin of unusual strong THz dielectric relaxation in paraelectric phase is discussed.
    Trvalý link: http://hdl.handle.net/11104/0202021