  Sr4Ru3O10 is a Ruddlesden-Popper compound with triple Ru-O perovskite layers
separated by Sr-O alkali layers. This compound presents a rare coexistence of
interlayer (c-axis) ferromagnetism and intralayer (basal-plane) metamagnetism
at ambient pressure. Here we report the observation of pressure-induced,
intralayer itinerant antiferromagnetism arising from the interlayer
ferromagnetism. The application of modest hydrostatic pressure generates an
anisotropy that causes a flattening and a tilting of RuO6 octahedra. All
magnetic and transport results from this study indicate these lattice
distortions diminish the c-axis ferromagnetism and basal-plane metamagnetism,
and induce a basal-plane antiferromagnetic state. The unusually large
magnetoelastic coupling and pressure tunability of Sr4Ru3O10 makes it a unique
model system for studies of itinerant magnetism.
