Dielectric and ultrasonic anomalies at 16, 37, and 65 K in SrTiO3

In this paper we report coincident anomalies in both dielectric response ac id sound velocities in strontium titanate around three temperatures 16, 37, and 65 K. The anomalies occur in both single-crystal specimens and ceramic s, so they cannot be related to grain boundary mechanisms, but they are enh anced by bismuth doping. The results indicate that the dielectric and ultra sonic anomalies are dynamic and not static. The physical nature of the anom alies was briefly discussed. [S0163-1829(99)06109-3].