Critical phenomena in perfect and inperfect TGS crystals

Abstract

Abstract The heat and elastic properties of TGS crystals grown above (type A) and below (type B) Tc were investigated. The critical anomalies of specific heat and sound velocity of type A crystals are closely follow Landau theory and should be considered as “perfect”. The type B crystals and small doses γ-irradiated type A crystals reveal the very similar critical anomalies which main features are the “tail” in paraelectric and small anomalous change of specific heat and sound velocity in ferroelectric phase. The thermal and elastic anomalies for both perfect and inperfect crystals obey Pippard-Janovec relations.