Pressure-induced transition from a charge-disproportionated antiferromagnetic state to a charge-uniform ferromagnetic state in Sr(2/3)La(1/3)FeO3.
The perovskite oxide Sr(2/3)La(1/3)FeO3 has been found to switch its electronic ground state drastically at 23 GPa through measurements of 57Fe Mössbauer spectroscopy and powder x-ray diffraction up to 56 GPa. In the low-pressure region a first-order transition from a charge-uniform paramagnetic metallic phase to a charge-disproportionated (3Fe(11/3+)-->2Fe(3+)+Fe5+) antiferromagnetic insulating phase occurs at 207 K at 0.1 MPa and 165 K at 21 GPa, typically. Above 25 GPa, however, a charge-uniform ferromagnetic (and most probably metallic) phase persists below 300 K. This switching occurs at a lattice volume of V(23 GPa)/V(0)(0.1 MPa) = 0.89.
Kawakami
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Department of Physical Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
Nasu
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Sasaki
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Kuzushita
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Morimoto
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Endo
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Yamada
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Kawasaki
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Takano
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