Magnetic field-induced transitions in geometrically frustratedCo3V2O8single crystal

Abstract

Magnetization and specific heat of the $S=3∕2$ antiferromagnet on a kagome staircase, ${\mathrm{Co}}_{3}{\mathrm{V}}_{2}{\mathrm{O}}_{8}$, were investigated as a function of temperature and magnetic field. The low temperature magnetization data revealed unusual features related to the strongly frustrated spin lattice. Of particular interest were magnetic field induced phase transitions observed for various orientations of the magnetic field. Abrupt macroscopic magnetization jumps induced by a magnetic field directed along the $\mathbit{c}$-axis have been observed below $6\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. This effect was also observed for a high enough magnetic field applied in the $\mathbit{a}\text{\ensuremath{-}}\mathbit{c}$ plane. It is suggested that the jump, observed for $H\ensuremath{\parallel}\mathbit{c}$ is due to a spin reorientation phase transition. It was shown that ${\mathrm{Co}}_{3}{\mathrm{V}}_{2}{\mathrm{O}}_{8}$ crystals are characterized by a strong magnetocrystalline anisotropy of an easy-plane type. This anisotropy is due to the presence of ${\mathrm{Co}}^{2+}$ ions in octahedral positions.