KTN的核磁共振研究

NMR STUDIES OF KTN

研究了掺Ｎｂ浓度为０．１５的ＫＴＮ晶体中１８１Ｔａ和９３Ｎｂ的核磁共振信号的线宽和（积分）强度对温度的依赖性。通过两种核的信息分析，我们观察到在１２０Ｋ－２３０Ｋ之间晶体发生二次相交，而且发现两种核的共振线的展宽起源是不同的。我们也把１８１Ｔａ的信号与两种标定纯的ＫＴａＯ３晶体的相应信号作了比较，发现“消除”效应都存在。

We have studied the temperature dependence of the NMR Linewidth and (integral)intensity of 181Taand 93Nb in a KTN crystal with a nominal Nb fraction 0.15. By analysing the information of the two typesof nuclei,we observed two time phase transitions between 120K-230K and concluded that the sources ofbroadening are different for them. The 181Ta signal has been compared to that of two nominally pureKTaO3-MIT and BS-89 crystals, the wipeout-effect exists in all three crystals.