Colossal magnetoresistance in La1−xLixMnO3

Abstract

La 1−x Li x MnO 3 (x=0, 0.1, 0.2, and 0.3) were synthesized by using conventional solid state reaction and partial melting technique. The compounds were determined to be of rhombohedral structure by x-ray powder diffraction. For the x=0.2 and x=0.3 samples, room temperature neutron powder diffraction patterns were collected and analyzed with the Rietveld method. The analysis showed that the Li substitutes onto the La site in the rhombohedral perovskite lattice. Resistivities were measured between 4.2 K and room temperature in the magnetic fields of 0, 1, 2, 4, 8, and 13 T. A wide semiconductor-metal transition at temperatures between 160 and 210 K or between 200–230 K were observed for both samples with x=0.2 and 0.3, respectively. Large magnetoresistances above 20%–80% were achieved at fields from null to 13 T over a wide temperature range from the ferromagnetic transitions down to 4.2 K. However, the x=0 and 0.1 samples show a semiconducting behavior in resistivity measured between 77 and 300 K.

Transport properties of Cs doped Pr2/3(Ba1−xCsx)1/3MnO3 manganites

“…They argued that smaller size of Li 1+ (0.78Å) is responsible for the peculiar behaviour of resistivity. Bhattacharya et al [25] noticed a decrease in T C and T P with Li doping in La 0.7 Ca 0.3−y Li y MnO 3 and their findings were similar to that of Wang et al [24]. Roy et al [26] reported the behaviour of Na 1+ doped La 1−x Na x MnO 3 (0.07 < x < 0.20).…”

“…So far, most of the studies have been focused towards the divalent alkaline-earth ion doped compounds. In contrast, there are few reports on the studies of monovalent alkali-metal doped samples [23][24][25][26][27][28][29][30][31]. These compounds were synthesized many years ago and tested as oxidation catalysts for exhausts gases for the internal combustion engines [32].…”

“…Boudaya et al [23] have studied the effect of the monovalent potassium substitution into the lanthanide sites in La 1−x K x MnO 3 (0.05 < x < 0.2) and observed that with K doping in LaMnO 3 , which is antiferromagnetic insulator develops a paramagnetic insulator-ferromagnetic metallic transition which further increases with K doping. On the contrary, Wang et al [24] found that the I-M transition and Curie temperature both decrease with Li 1+ doping in La 1−x Li x MnO 3 (0 < x < 0.3). They also noticed two insulator-metal transitions in the ρ-T behaviour.…”

Nd doping induced simultaneous magnetic and electronic transition in La0.83−xNdxKyMnO3

“…The sample exhibited a special transport behavior [7,8], it shows that there were double peaks or shoulder in the temperature dependence of resistivity measurement. This phenomenon was initially explained by a possible phase inhomogeneity in La 1Àx A x MnO 3 (A=K, Na) sample due to their sintering in short time [9,10]. However, the second resistivity peak could not be removed no matter what synthesis techniques was used, either by preparing the bulk sample in a long sintering time or making thin film [9][10][11].…”

Effect of Li addition on structural, electrical and electrochemical properties on lanthanum manganite

“…However, monovalent cations, such as Li were seldom investigated as dopants of LaMnO 3 [4][5][6][7][8][9][10]. Therefore, in this study, various amounts of Li ions were substituted for La in LaMnO 3 using a solid state reaction method.…”