Anisotropy of magnetoresistivities in Sr$_{3}$Ru$_{2}$O$_{7}$: Evidence for orbital-dependent metamagnetism*

Sr$_{3}$Ru$_{2}$O$_{7}$ has been studied extensively due to its rich electronic and magnetic ground state properties, such as its quantum criticality and electronic nematic phase [1,2]. In this talk we will present the results of in-plane angle-resolved directional magnetotransport anisotropy measurements, a technique we used previously to elucidate the orbital-selective nature of the itinerant metamagnetism in Sr$_{4}$Ru$_{3}$O$_{10}$ [3]. We find that the \textit{c}-axis magnetoresistivity anisotropy undergoes a drastic change in symmetry from fourfold to twofold through the metamagnetic transition, consistent with the behavior expected for the strong spin polarization. In contrast, the in-plane magnetoresistivity anisotropy remains fourfold through the transition accompanied by only a gradual shift in phase, and only trends towards twofold symmetry at fields well above the transition. These findings suggest the $d_{xz,yz}$ bands, should play a pivotal role in the metamagnetic transition.\\[4pt] [1] S. Grigera \textit{et al}., Science \textbf{294}, 329 (2001)\\[0pt] [2] R. Borzi \textit{et al}., Science \textbf{315}, 214 (2007)\\[0pt] [3] D. Fobes \textit{et al}., Phys. Rev. B \textbf{81}, 172402 (2010)