ESR-study of the low-temperature phase transition in KDy(WO 4) 2

Abstract

The low-temperature structural phase transition of the Jahn-Teller type in a KDy(WO 4) 2 single crystal has been studied by means of the ESR method. The ESR line width near the point of transition ( T spt≈7 K) is shown to increase from 0.17 T up to a maximum value of 0.24T and then it decreases to 0.19 T. The width of transition area is about 8 K. The symmetry of g-tensor does not change at the point of the phase transition while the values of the g-tensor components change considerably: g z =3.13; g x ≈0; g y =0.82 at T > T spt; g z =1.98; g x ≈0; g y =1.19 at T < T spt. It is suggested that the symmetry of high- and low-temperature phases is identical.