Netsu Sokutei, 36 (4), p. 189, (2009)

2008 年度日本熱測定学会奨励賞

強相関電子系遷移金属酸化物における 特異な電子・磁気相図の熱力学的研究

Exploration of Novel Electronic and Magnetic Phase Diagrams in Transition Metal Oxides by Heat Capacity Measurements

Transition metal oxides with strong electron correlation show a variety of unusual properties. Establishing the electronic and magnetic phase diagrams as a function of composition and temperature is a first step in understanding their behavior, and sometimes a crucial step in discovering novel properties. This article reviews phase-diagram studies on RCoO3, RMnO3, RMn2O5, and Y2 -x BixRuO7 (R = rare earth), where heat capacity measurements were instrumental in identifying the phase transitions and understanding the complex properties. High-pressure synthesis and synchrotron powder x-ray structural analysis also played important roles in constructing and understanding the phase diagrams.