2 2 M ar 1 99 9 Optical Investigations of Charge Gap in Orbital Ordered
نویسندگان
چکیده
Temperature and polarization dependent electronic structure of La1/2Sr3/2MnO4 were investigated by optical conductivity analyses. With decreasing temperature, for E ‖ ab, a broad mid-infrared (MIR) peak of La1/2Sr3/2MnO4 becomes narrower and moves to the higher frequency, while that of Nd1/2Sr3/2MnO4 nearly temperature independent. We showed that the MIR peak in La1/2Sr3/2MnO4 originates from orbital ordering associated with CE-type magnetic ordering and that the Jahn-Teller distortion has a significant influence on the width and the position of the MIR peak. PACS number; 71.15.Fv, 71.45.Lr, 75.50.Ee, 78.20.Ci Typeset using REVTEX
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