Nonbolometric photoresponse in (La,Pr)0.67Ca0.33MnO3 thin films -: art. no. 052504

We have studied light-induced resistance changes (photoresponse) in the colossal magnetoresistive manganite material (La,Pr)(0.67)Ca0.33MnO3. The metal-insulator transition in this material is understood to be driven by the percolation of the metallic channel in an inhomogeneous matrix of insulating and metallic components. Our experiments reveal a nonthermal (nonbolometric) component of the light-induced resistance change, in addition to the expected resistance change related to heating (bolometric effect). This nonthermal component is seen only in the metal-insulator transition region. Our results suggest that this component may be associated with the light-induced resistance decrease in the insulating regions through an electronic mechanism. (c) 2006 American Institute of Physics.