Multiple magnetic transitions in multiferroic BiMnO3

摘要: The magnetic phase variations under hydrostatic pressure on multiferroic ${\text{BiMnO}}_{3}$ have been examined by the dc magnetization $[{M}_{g}(T)]$, hysteresis $[{\ensuremath{\mu}}_{eff}(H)]$, and ac susceptibility $[{\ensuremath{\chi}}_{g}^{\ensuremath{'}}(T)]$. Three transitions, manifested as kinks I, II, III ${M}_{g}(T)$ curves, were identified at 8.7 9.4 kbar. With increasing pressure, transition temperatures of kink I II (${T}_{k\text{I}}$ ${T}_{k\text{II}}$) tend to decrease, but temperature $({T}_{k\text{III}})$ showed more complex variation. Under field, ${T}_{k\text{I}}$ ${T}_{k\text{II}}$ increase; however, ${T}_{k\text{III}}$ decreases. Combining curves with ${\ensuremath{\mu}}_{eff}(H)$ ${\ensuremath{\chi}}_{g}^{\ensuremath{'}}(T)$, detailed properties these three would be shown follows. Kink is a long-range soft ferromagnetic which occurs ${T}_{k\text{I}}\ensuremath{\sim}100\text{ }\text{K}$ ambient suppressed completely 11.9 emerges kbar along ${T}_{k\text{II}}\ensuremath{\sim}93\text{ also canted in nature. III, antiferromagnetic transition, appears ${T}_{k\text{III}}\ensuremath{\sim}72.5\text{ proposed diagrams show different features ${\text{BiMnO}}_{3}$. These findings are believed result from crystal structure influenced external pressure. results indicate common complicated correlation between lattice distortion spin configuration system.