Raman spectra in the antiferromagnetic insulator phases of s = 1/2 high Tc superconducting cuprates were compared with s = 1 La2NiO4. The anomalous magnon spectra in cuprates suggest that the four-spin cyclic exchange interactions are very large. The doped carriers in cuprates show non-Fermi liquid behavior.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics