TY - JOUR
T1 - Magnetotransport properties of a room temperature rectifying tunnel junction made of electron and hole doped manganites
AU - Mitra, C
AU - Kobernik, G
AU - Dorr, K
AU - Muller, KH
AU - Schultz, L
AU - Raychaudhuri, Pratap
AU - Pinto, R
AU - Wieser, E
PY - 2002/1/1
Y1 - 2002/1/1
N2 - The hole-doped (p) manganite La0.7Ca0.3MnO3 and the electron-doped (n) manganite La0.7Ce0.3MnO3 undergo an insulator-to-metal transition at around 250 K, above which both behave as a polaronic semiconductor. We have fabricated an epitaxial trilayer (La0.7Ca0.3MnO3/SrTiO3/La0.7Ce0.3MnO3), where SrTiO3 is an insulator. At room temperature, i.e., in the semiconducting regime, it exhibits asymmetric current-voltage (I-V) characteristics akin to a p-n diode. The observed asymmetry in the I-V characteristics disappear at low temperatures where both the manganite layers are metallic. The I-V curves exhibit an intriguing temperature dependence in the presence of magnetic field. At room temperature, i.e., above the ordering temperature, we have a negative magnetoresistance (MR) and at low temperature we have a positive MR, indicative of a minority spin carrier band in La0.7Ce0.3MnO3. A possible mechanism for the observed effects are discussed. (C) 2002 American Institute of Physics.
AB - The hole-doped (p) manganite La0.7Ca0.3MnO3 and the electron-doped (n) manganite La0.7Ce0.3MnO3 undergo an insulator-to-metal transition at around 250 K, above which both behave as a polaronic semiconductor. We have fabricated an epitaxial trilayer (La0.7Ca0.3MnO3/SrTiO3/La0.7Ce0.3MnO3), where SrTiO3 is an insulator. At room temperature, i.e., in the semiconducting regime, it exhibits asymmetric current-voltage (I-V) characteristics akin to a p-n diode. The observed asymmetry in the I-V characteristics disappear at low temperatures where both the manganite layers are metallic. The I-V curves exhibit an intriguing temperature dependence in the presence of magnetic field. At room temperature, i.e., above the ordering temperature, we have a negative magnetoresistance (MR) and at low temperature we have a positive MR, indicative of a minority spin carrier band in La0.7Ce0.3MnO3. A possible mechanism for the observed effects are discussed. (C) 2002 American Institute of Physics.
UR - http://www.scopus.com/inward/record.url?scp=0037095199&partnerID=8YFLogxK
U2 - 10.1063/1.1451842
DO - 10.1063/1.1451842
M3 - Article
VL - 91
SP - 7715
EP - 7717
JO - Journal of Applied Physics
JF - Journal of Applied Physics
IS - 10
ER -