Dilatometric study of the metamagnetic and ferromagnetic phases in the triple-layered Sr4Ru3O10 system

High-resolution thermal expansion and magnetostriction measurements were performed on single crystalline Sr4Ru3O10 in the temperature range T = 2-200 K and magnetic fields up to 12 T. Signatures of the ferromagnetic phase transition at T-c similar to 102 K were found in the lattice expansion of both the c axis and the ab plane. Due to the layered crystal structure the effects are, however, strongly anisotropic. Further distinct anomalies are visible in the lower temperature region, which could be correlated with the metamagnetic transition at T* similar to 50 K. By relating the changes of the thermal expansion at the ferromagnetic transition to those of the heat capacity via the Ehrenfest relation, a strong volumetric pressure dependence of dT(c)/dp similar to -8.5 K/GPa has been revealed.