Complex Phase Behavior of Exotic Oxides: Optical Spectroscopy Studies

123 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2001.We observed that the metal-insulator transition in Ca3Ru 2O7 is characterized by the opening of correlation charge gap. The out-of-phase c-axis oxygen vibration phonon mode is seen to be closely associated with the metal-insulator transition possibly by modulating the bandwidth of the system. We also observed Raman scattering from two-magnon excitations in the antiferromagnetic phase of Ca3Ru 2O7, from which we could estimate the in-plane spin-spin exchange coupling constant J∥. Importantly, we found that Ca3Ru2O7 does not exhibit strong in-plane magnetic correlations above TN.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD