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https://www.ias.ac.in/article/fulltext/pram/058/05-06/1089-1092

Thin films; magnetoresistance; magnetization

Epitaxial La_0.2Nd_0.4Ca_0.4MnO₃ thin films have been deposited at 800°C on LaAlO₃ substrate using pulsed laser deposition technique. The structural and magnetotransport properties of the films have been studied. The sharp peak in the temperature dependence of the resistance corresponding to metal-to-insulator transition (T_p) has been observed at a temperature of T_p=82 K, 97 K and 110 K for 0 Oe, 20 kOe and 40 kOe magnetic fields, respectively. The film exhibits a large nearly temperature-independent magnetoresistance around 99% in the temperature regime below T_p. The zero field-cooled (ZFC) and field-cooled (FC) magnetization data at 50 Oe shows irreversibility between the ZFC and FC close to the ferromagnetic transition temperature T_c=250 K. The ZFC temperature data of the film displays ferromagnetic behavior for higher temperature regime T_c=250 K>T>T_p=82 K, and a decrease in magnetization with decreasing temperature up to 5 K below 82 K exhibiting a sort of antiferromagnetic behavior in the low temperature regime (T<82 K=T_p=T_N).

Darshan C Kundaliya¹ A A Tulapurkar² J John² R Pinto² R G Kulkarni¹

1. Department of Physics, Saurashtra University, Rajkot - 360 005, India
2. Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai - 400 005, India