Yttrium barium copper oxide system, which undergoes a metal-to-insulator transition under variation of carrier concentration, was investigated using Raman spectroscopy. The intensity of CuO2-plane phonon modes decreased as the system approached the metal-to-insulator phase boundary and it scaled with the inverse of the hole concentration within the CuO2 conducting planes. The CuO2-plane mode intensity and transition temperature for the oxides was found to be correlated. It was found that a simple and useful probe for metal-to-insulator transition and carrier dynamics in the CuO2 plane for substituted materials was provided by this correlation and the CuO2-plane mode intensity.
ASJC Scopus subject areas