Phase transition in the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mn>5</mml:mn><mml:msup><mml:mrow><mml:mi>d</mml:mi></mml:mrow><mml:mn>1</mml:mn></mml:msup></mml:mrow></mml:math> double perovskite <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>Ba</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi>CaReO</mml:mi><mml:mn>6</mml:mn></mml:msub></mml:mrow></mml:math> induced by high magnetic field
Hajime Ishikawa, Daigorou Hirai, Akihiko Ikeda, Masaki Gen, Takeshi Yajima, Akira Matsuo, Yasuhiro H. Matsuda, Zenji Hiroi, Koichi Kindo
Abstract
Magnetic properties of an antiferromagnetic double perovskite oxide ${\mathrm{Ba}}_{2}{\mathrm{CaReO}}_{6}$, where ${\mathrm{Re}}^{6+}$ $(5{d}^{1})$ ions with large spin-orbit coupling are arranged on the face-centered-cubic lattice, are investigated using pulsed high magnetic field up to 66 T. Magnetization and magnetostriction measurements have revealed a magnetic field-induced phase transition at around 50 T. The phase transition accompanies a jump of magnetization and longitudinal magnetostriction of approximately $2\ifmmode\times\else\texttimes\fi{}{10}^{--4}$ with the change of power-law behavior, indicating sizable coupling between the electronic degrees of freedom and the lattice. The high-field phase exhibits a magnetic moment approximately 0.2 ${\ensuremath{\mu}}_{\mathrm{B}}$, which is close to the values observed in $5{d}^{1}$ double perovskite oxides with noncollinear magnetic structure. We argue that ${\mathrm{Ba}}_{2}{\mathrm{CaReO}}_{6}$ is an antiferromagnet that sits close to the phase boundary between the collinear and noncollinear phases, providing the target material for investigating the interplay between spin-orbital entangled electrons and magnetic field.