Structural, magnetic and magneto-transport properties of Pr_(0.5)Ca_(0.5)Mn_(0.9)V_(0.1)O_3: Indication of large field coefficient of resistance (FCR)

摘要

Structural, magnetic and magneto-transport properties of polycrystalline Pr_(0.5)Ca_(0.5)Mn_(0.9)V_(0.1)O_3 have been studied. The incorporation of vanadium attributes to enhancement in the Mn~(3+)/Mn~(4+) ratio as well as density of conducting e_g carriers, which affects the magnetic and electrical behavior of the system. On cooling, a multiphase separated "paramagnetic (PM) - charge-ordered antiferromagnetic (COAFM) - ferromagnetic (FM) -reentrant spin glass (RSG)" phases are observed with the characteristic charge ordering temperature T_(CO) = 233 K and Neel temperature T_N = 143 K. Field-induced first-order magnetic phase transition from a charge-ordered antiferromagnetic state to a ferromagnetic cluster glass state takes place at T_C = 44 K. A 7 T magnetic field induces metal-insulator transition at T_(MI) = 163 K. At low temperatures, strong memory-effect and colossal magnetoresistance (CMR) ～ 99.99% are observed in resistivity data. The sample shows a high field coefficient of resistance (FCR) value of about 855% in the low-temperature regime.