Reactance of the n-Au/p-La0.67Ca0.33MnO3 film contact

Artikel i vetenskaplig tidskrift, 2006

The responses of the resistance and reactance of Au/(20 nm)La 0.67Ca0.33MnO3 film heterostructures to temperature variation and magnetic field (f = 100 kHz) are investigated. At T = 300 K, the capacitance per unit area of the interface between a gold contact and the Au/(20 nm)La0.67Ca0.33MnO3 epitaxial film is found to be about 1 μF/cm2. The maximum value of the negative magnetoreactance (≈60% at μ0 H = 0.4 T) of the heterostructures is almost twice as high as the extremal value of the active magnetoresistance at T ≈ 235 K. The effective depth of magnetic field penetration into the manganite film on the side of the gold contact deposited on its surface is about 3 nm at room temperature. © Pleiades Publishing, Inc., 2006.