Photo-induced magnetism of Pr0.65Ca0.35MnO3 in powder and thin films

Abstract

ABSTRACTThe photo-induced magnetism was originally found in Pr0.65Ca0.35MnO3 powder by the ESR and x-ray diffraction studies. However, the mechanism of the photo-induce magnetism was under cover for a long time. Now, D.C. magnetization measurement under a near infrared pulsed laser irradiation (hν = 1.18 eV) reveals the mechanism. The D.C. magnetization prominently increases (approximately 6 %) under the laser irradiation, especially around 90 K near the canted antiferromagnetic (CAF) – antiferromagnetic (AF) transition. The result is consistent with the previous studies and indicates that a CAF – ferromagnetic transition is caused associating with the charge-order (CO) – charge-delocalize (CD) (insulator – metal) transition by the laser irradiation. As the second step for development, the thin films were prepared with the pellet of Pr0.65Ca0.35MnO3 in the on-axis and off-axis geometry of RF magnetron sputtering deposition. The off-axis geometry provides the Pr0.65Ca0.35MnO3 film same as powder composition and the on-axis sputtering fortunately provides the Pr0.99Ca0.01MnO3 film. Both films show photo-induced magnetism. The present photo-induced magnetism is coming from a spin-canted phase in both compounds.