Fyzikální ústav Akademie věd ČR

Seminář Úterý, 02.06.2015 10:00 - 11:00

Přednášející: Prof. B. Dabrowski (Dept. of Physics, Northern Illinois University, USA)
Místo: Přednáškový sál FZU na Slovance
Jazyk: anglicky
Pořadatelé: Oddělení dielektrik

Abstract (abbreviated by J. Hlinka, full version enclosed):

Until only recently, it was proven challenging to achieve the displacive ferroelectric distortion in the d³ manganites because the [Mn⁴⁺-O] bonds have not been put under sufficient tension. By advancing elaborate synthesis processes, which are necessary to avoid the more stable hexagonal polymorphs, we were recently able to extended the substitution limit of the large size Ba ion in bulk Sr_1-xBa_xMnO₃ samples to x = 0.45 with two-step “in situ” synthesis in a thermogravimetric furnace in flowing H₂/Ar gas followed by oxygen anneal. The achieved perovskite ceramics exhibit ferroelectricity (T_F > 300 K) and G-type antiferromagnetism (T_N ~ 200 K) originating exclusively from the Mn cations.

Přílohy:

Abstract (full version)