Dielectric behavior of paraelectric KTaO3 , CaTiO3, and „Ln1Õ2Na1Õ2...TiO3 under a dc electric field
نویسندگان
چکیده
The dc electric-field dependence of dielectric constant in the paraelectrics, KTaO3 single crystals, CaTiO3 and (Ln1/2Na1/2)TiO3 (Ln5La and Nd! ceramics is studied at cryogenic temperatures in the dc electric-field range 0–60 kV/cm. The results indicate that KTaO3 possesses a high tunability K$5@e(E0)2e(E)#/e(E0) 5;50%% at 20 kV/cm, and low dielectric loss tan d (;0.003); while CaTiO3 and (Ln1/2Na1/2)TiO3 (Ln 5La and Nd! show low tunability of ;1% and ;0.1%, respectively, at 20 kV/cm; however, the dielectric loss tan d is very small (;0.0004–0.003). The possible physical mechanism of the behavior observed is discussed.
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