MBE growth and characterization of A-site deficient, low-field magnetoresistance (Pr/sub 1-x/Sr/sub x/)/sub y/MnO/sub 3-/spl delta// oriented thin films

There has been renewed activities recently in studying the magnetotransport properties of doped manganese perovskite thin films L/sub 1-x/A/sub x/MnO/sub 3-/spl delta// (L=La,Pr; A=Ca,SrBa), owning to both the rich variety of physical properties they possess and their promising applications. While most efforts were devoted to the stoichiometric Li/sub 1-x/A/sub x/MnO/sub 3-/spl delta// phases, those phases deviated from stoichiometry are also attracting increasing interests because they exhibit more interesting properties such as different phase transition temperatures and marked low field magnetoresistance, and the most important, they offer other degree of freedom to adjust the properties of these materials. It was reported that stoichiometric thin films were usually obtained with such methods as pulsed laser deposition (PLD), sputtering, chemical vapor deposition (CVD) and metal organic chemical vapor deposition (MOCVD). We report on the growth and structural, electric and magnetotransport characterizations of epitaxial (Pr/sub 1-x/Sr/sub x/)/sub y/MnO/sub 3-/spl delta// thin films grown by oxygen plasma assisted molecular beam epitaxy (MBE).