La_(0.67)Ba_(0.33)MnO_3薄膜的激光辐照效应研究

Effect of laser irradiation on La_(0.67)Ba_(0.33)MnO_3 thin films

利用脉冲激光沉积技术在LaAlO3(00l)单晶衬底上制备了La0.67Ba0.33MnO3薄膜,研究了CO2激光辐照对La0.67Ba0.33MnO3薄膜的微结构和磁电性能的影响.结果表明,经激光辐照后,La0.67Ba0.33MnO3薄膜的结晶性增强,薄膜应变减小;薄膜表面形貌由"岛状"结构变为"平原"结构,且粗糙度大大降低;同时,薄膜的饱和磁化强度、铁磁居里温度、金属—绝缘态转变温度和磁电阻增大,而矫顽场和电阻率减小.根据对传统退火效应的分析和理论计算,认为激光辐照导致的表面微结构的变化以及薄膜的氧含量和均匀性的提高对La0.67Ba0.33MnO3薄膜的磁电性能的改善与优化密切相关.

La 0.67 Ba 0.33 MnO3 thin films were grown on LaAlO3 substrate using pulsed laser deposition. The microstructure,magnetic and electrical properties of as-grown,annealed and CO2-laser-irradiated （CLI） LBMO films were studied. It is found that,after laser irradiation,the enhancement of the crystallinity of the film is accompanied by the emergence of the plain-like surface morphology with smaller roughness. The structure and magneto-transport properties of LBMO films are markedly improved in several dozens of seconds via CO2 laser irradiation. Compared with the annealing treatment,laser irradiation is a fast and effective way to tailor CMR manganites for industrial applications.