Phase diagram and isotope effect in cobaltites with spin-state transitions |
| |
| Authors: | N A Babushkina A N Taldenkov A V Kalinov L M Fisher O Yu Gorbenko J Rohrkamp T Lorenz D I Khomskii and K I Kugel |
| |
| Institution: | 1.Russian Research Center Kurchatov Institute,Moscow,Russia;2.All-Russian Electrical Engineering Institute,Moscow,Russia;3.Moscow State University,Moscow,Russia;4.II. Physikalisches Institut,Universit?t zu K?ln,K?ln,Germany;5.Institute for Theoretical and Applied Electrodynamics,Russian Academy of Sciences,Moscow,Russia |
| |
| Abstract: | The oxygen isotope effect was investigated in cobalt oxides (Pr1 − y
Eu
y
)0.7Ca0.3CoO3 (0.12 < y < 0.26). The measurements of magnetization, electric resistivity, differential magnetic susceptibility, thermal expansion,
and specific heat show that as the Eu concentration increases, a transition from “ferromagnetic metal” to “weakly magnetic
insulator” is observed at y ≈ 0.18. In the insulating ground state, the transition occurs with a Co spin-state change that is suppressed in the ferromagnetic
(FM) metallic phase. The spin-state transition at y > 0.18 is accompanied by a substantial oxygen isotope effect that is virtually absent in the FM phase (y < 0.18). |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
