Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

We have performed magnetostriction and ultrasound measurements on the quasi-one-dimensional S ¼ 1=2 Ising-like antiferromagnet BaCo₂V₂O₈ in high magnetic fields of up to 51 T. The magnetostriction shows lattice shrinking along the c-axis, and we interpret it as the lattice distortion caused by exchange striction and Van-Vleck paramagnetism. It is clarified that the field dependence of sound velocity is correlated to the magnetostriction. We observed a pronounced softening in the sound velocity of the longitudinal-acoustic c₃₃ mode and found a novel phase transition.