Magnetic analog of the Fulde-Ferrell-Larkin-Ovchinnikov phase in Sr 3 Ru 2 O 7

Abstract

The phase diagram of Sr3Ru2O7 contains a metamagnetic transition that bifurcates to enclose an anomalous phase with intriguing properties—a large resistivity with anisotropy that breaks the crystal-lattice symmetry. We propose that this is a magnetic analog of the spatially inhomogeneous superconducting Fulde-Ferrell- Larkin-Ovchinnikov state. Based on a microscopic theory of Stoner magnetism, we derive a Ginzburg-Landau expansion where the magnetization transverse to the applied field can become spatially inhomogeneous. We show that this reproduces the observed phase diagram of Sr3Ru2O7.