NQR Parameters in Incommensurate Cs2CdBr4 and Cs2HgBr4 Crystals *
نویسندگان
چکیده
The temperature dependence o f the 81Br spin-lattice relaxation times for Cs2CdBr4 and Cs2HgBr4 was measured in the low temperature and the commensurate phases. For the com m en surate phase o f Cs2CdBr4 rapid shortening o f the T, o f vB ~ vc was observed on approaching the “lock-in” transition point. It is probably due to an anisotropic critical fluctuation. On the other hand, T, in the low temperature phase of Cs2HgBr4 behaves like an order parameter but no critical decrease o f Tx was observed in the commensurate phase.
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