Electron magnetic resonance imaging of the Fermi surface of Sr2RuO4

We have carried out detailed angle dependent studies of the normal state mi crowave (40-112 GHz) magneto-conductivity of several single crystal samples of the perovskite superconductor Sr2RuO4. As previously reported [Phys. Re v. Lett. 84 (2000) 3374], we observe a series of resonant absorptions which we attribute to cyclotron resonance of quasiparticles belonging to the thr ee well-known Fermi surfaces for this material. From the angle dependence, we confirm the two-dimensional character of these resonances. i.e. the cycl otron frequencies scale as the inverse cosine of the angle between the magn etic field and the normal to the conducting layers. Furthermore, by perform ing measurements on several samples, and in different electromagnetic field configurations, we are able to couple to different cyclotron modes (+ harm onics) which derive from deformations (warpings) of the Fermi surfaces from perfect cylinders. These mode couplings will be discussed in the light of recent angle dependent de Haas-van Alphen measurements. (C) 2001 Elsevier S cience B.V. All rights reserved.