ABSTRACT
We have observed cyclotron resonance in the layered perovskite superconductor Sr2RuO4. We obtain cyclotron masses for the alpha, beta, and gamma Fermi surfaces of (4.33+/-0.05)m(e), (5.81+/-0. 05)m(e), and (9.71+/-0.2)m(e), respectively. The appreciable differences between these results and those obtained from de Haas-van Alphen measurements are attributable to strong electron-electron interactions in this system. Our findings appear to be consistent with predictions for an interacting Fermi liquid; indeed, semiquantitative agreement is obtained for the electron pockets beta and gamma.
ABSTRACT
The effects of finite temperature and noninteracting spins on magnetic breakdown (MB) in a quasi-two-dimensional organic conductor have been determined by computing the field-dependent free energy using a realistic crystal structure with no adjustable parameters. The de Haas-van Alphen oscillation spectra, including the MB phenomena, are thereby obtained microscopically. Within the range of computed magnetic field, from 170 to 1400 T, we find remarkable agreement between the predictions of the semiclassical and quantum treatment. We also find that the Zeeman effect leads to splitting of a frequency corresponding to the fundamental orbit.
