In-depth study of the H−T phase diagram of Sr4Ru3O10 by magnetization experiments

We present magnetization measurements on Sr4Ru3O10 as a function of temperature and magnetic field applied perpendicular to the magnetic easy c-axis inside the ferromagnetic phase. Peculiar metamagnetism evolves in Sr4Ru3O10 below the ferromagnetic transition T-C as a double step in the magnetization at two critical fields H-c1 and H-c2. We map the H - T phase diagram with special focus on the temperature range 50 K <= T <= TC. We find that the critical field H-c1(T) connects the field and temperature axes of the phase diagram, whereas the Hc2 boundary starts at 2.8 T for the lowest temperatures and ends in a critical endpoint at (1 T; 80 K). We conclude from the temperature dependence of the ratio H-c1/H-c2(T) that the double metamagnetic transition is an intrinsic effect of the material and it is not caused by sample stacking faults such as twinning or partial in-plane rotation between layers.