Theoretical investigations on electrocaloric properties of(111)-oriented PbMg_(1/3)Nb_(2)/3O_(3) single crystal

摘要

The electrocaloric(EC)effect accompanied with the ferroelectric to paraelectric phase transition in(111)-oriented PbMg_(1/3)Nb_(2)/3O_(3)(PMN)is investigated.It is shown that the largest change TDis 0.37 K in 3 kV/cm electric field shift near the Curie temperature of 221 K;that is,the cooling TDper unit field(MV/m)is 1.23×10^(-6) m·K/V.This value is significantly larger,and comparable with the value of 0.254×10^(-6) m·K/V for PbZr_(0.95)Ti_(0.05)O_(3)thin film under larger electric field shift ED=30 kV/cm.Thus,the EC effect of(111)PMN single crystal provides cooling solutions at low temperatures,and opens more opportunities for practical application in cooling systems.