Uniaxial-pressure induced ferromagnetism of enhanced paramagnetic Sr3Ru2O7

We report a uniaxial pressure-dependence of magnetism in layered perovskite strontium ruthenate Sr3Ru2O7. By applying a relatively small uniaxial pressure, greater than 0.1 GPa normal to the RuO2 layer, ferromagnetic ordering manifests below 80K from the enhanced-paramagnet. Magnetization at 1 kOe and 2 K becomes 100 times larger than that under ambient condition. Uniaxial pressure dependence of Curie temperature T-C suggests the first order magnetic transition. Origin of this uniaxialpressure induced ferromagnetism is discussed in terms of the rotation of RuO6 octahedra within the RuO2 plane.