Temperature dependence of the EPR line width and a relaxation of Cr³⁺ ions in ZnWo₄

Abstract

The change of the EPR line width, shape, and angular dependence of the halfwidth of Cr3+ ions in ZnWO, is investigated in the temperature range from 4.2 to 1200 OK. It is shown that the EPR line broadening at high temperatures is due to the spin-phonon interaction. Two-and four-phonon processes of Raman-type play t,he main part in relaxation. Experimental data on high-temperature line broadening are used to evaluate the spinlattice relaxation time at liquid helium temperature.HbI JIHHHII 3IIP HOHOB W + B ZnWO, B mnepsane TeMnepaTyp OT 4,2 AO 1200 OK.IIo~aaaao, YTO paclutipeHHe JIHHHII 3nP n p~ BHCOKE~X TeMnepaTypax 06ycnoBneHo II qempex-I$oHoHHme nporreccm paMaHoBcKoro Tma. 3~c n e p a~e~~a~r b~m e AaH-Hbie no ymnpeHmo JIIIHAA 3IIP npx BHCOIFHX Tenmepa-rypax W C~O J I~~O B~H~ nnx OueHKH BpeMem cnm-perueTosHoi penaKcasm n p~ TeMnepaType xnmoro renm.