Study of Dipole Ordering in K1-xLixTa1-yNbyO3by Raman Spectroscopy

Recently, very intriguing dipole-ordering phenomena near the critical temperature and down into the low temperature phase were reported for K{sub 1-x}Li{sub x}Ta{sub 1-y}Nb{sub y}O{sub 3}. The understanding of these processes is a crucial aspect of basic research and applications. In the present work, we report on Raman experiments in K{sub 1-x}Li{sub x}Ta{sub 1-y}Nb{sub y}O{sub 3} crystals with x -0.004 and y -0.031. Systematic analysis of TO{sub 1} and TO{sub 4} spectra within the temperature range of 17-150 K was performed. All the measurements were performed after both zero-field and field cooling. The results enable us to gain new evidence of the competition between long-range order and the Li-related dipole glasslike subsystem.