Magnetoelastic coupling across the metamagnetic transition in Ca$_{2-x}$Sr$_x$RuO$_4$ (0.2 < x < 0.5)

J. Baier; P. Steffens; O. Schumann; M. Kriener; S. Stark; H. Hartmann; O. Friedt; A. Revcolevschi; P. G. Radaelli; S. Nakatsuji; Y. Maeno; J. A. Mydosh; T. Lorenz; M. Braden

doi:10.1007/s10909-007-9330-0

paper

Magnetoelastic coupling across the metamagnetic transition in Ca $_{2 - x}$ Sr $_{x}$ RuO $_{4}$ (0.2 < x < 0.5)

arXiv:cond-mat/0610769 · doi:10.1007/s10909-007-9330-0

Abstract

The magnetoelastic coupling in Ca $_{1.8}$ Sr $_{0.2}$ RuO $_{4}$ and in Ca $_{1.5}$ Sr $_{0.5}$ RuO $_{4}$ has been studied combining high-resolution dilatometer and diffraction techniques. Both compounds exhibit strong anomalies in the thermal-expansion coefficient at zero and at high magnetic field as well as an exceptionally large magnetostriction. All these structural effects, which are strongest in Ca $_{1.8}$ Sr $_{0.2}$ RuO $_{4}$ , point to a redistribution of electrons between the different $t_{2 g}$ orbitals tuned by temperature and magnetic field. The temperature and the field dependence of the thermal-expansion anomalies in Ca $_{1.8}$ Sr $_{0.2}$ RuO $_{4}$ yield evidence for a critical end-point lying close to the low-temperature metamagnetic transition; however, the expected scaling relations are not well fulfilled.

17 pages, 7 figures

Magnetoelastic coupling across the metamagnetic transition in Ca2−x​Srx​RuO4​ (0.2 < x < 0.5)

Abstract

Magnetoelastic coupling across the metamagnetic transition in Ca $_{2 - x}$ Sr $_{x}$ RuO $_{4}$ (0.2 < x < 0.5)