Colossal and constant magnetoresistance over a large temperature range between 230 and 4.2 K in La0.8Li0.2MnO3 prepared by a partial melting technique

La0.8Li0.2MnO3 was prepared by a partial melting technique. The Li-doped LaMnO3 compound has a rhombohedral perovskite structure and shows a wide semiconductor-to-metal transition between 230 and 175 K in resistance versus temperature. Nearly constant magnetoresistance, Δρ/ρ0, above 20-60% was achieved with application of magnetic fields from 1 to 8 Tesla (T) over a very large temperature range from the ferromagnetic transition at 230-4.2 K. As a comparison, a partial melted La0.7Ca0.3MnO3 shows a very narrow ferromagnetic transition around 230 K which is the same as that of single crystals and epitaxy thin films. © 1998 Elsevier Science S.A.