Cu掺杂La0.67Sr0.33CuxMn1-xO3薄膜的光诱导效应研究

分别采用溶胶-凝胶和射频磁控溅射的方法制备了La_0.67Sr_0.33Cu_xMn_1-xO₃（x=0.05, 0.10和0.15）系列块材和薄膜，研究了Cu部分替代对薄膜光诱导特性的影响.实验结果表明随着Cu掺杂量的增加，薄膜的金属-绝缘转变温度向低温方向移动，且导电性降低.在金属相激光作用诱导电阻增大.光致电阻相对变化极大值随着Cu含量的增加而增大，当 关键词： 锰氧化物 光诱导 Cu掺杂 晶格效应

Photoinduced effect in Cu doping La0.67Sr0.33Cux Mn1-xO3 thin films

The compounds and films of La_0.67Sr_0.33Cu_xMn_1-xO₃（x= 0.05, 0.10, and 0.15） were prepared using the sol-gel technique and an RF magnetron sputtering method, respectively. The effect of Cu doping on the photoinduced properties of La_0.67Sr_0.33Cu_xMn_1-xO₃ films was investigated. Experimental results indicate that the increasing Cu doping content leads to a decrese of the insulator-metal transition temperature and an increase of the resistance. The laser irradiation induces an increase of the resistance in the metallic state. The maximum values of the photoinduced relative change in the resistance increase with increasing x, and it reaches 58.3％ at x =0.15. The intriguing mechanism of the photoinduced effect on the resistance was discussed, which may be the photoinduced electrons being trapped at a localized state outside the CuO₂ planes in combination with and the lattice effect.