Colossal magnetoresistance

About: Colossal magnetoresistance is a research topic. Over the lifetime, 3658 publications have been published within this topic receiving 130104 citations.

Parallel magnetic field induced giant magnetoresistance in low density quasi-two-dimensional layers

Abstract: We provide a possible theoretical explanation for the recently observed giant positive magnetoresistance in high mobility low density quasi-two-dimensional electron and hole systems. Our explanation is based on the strong coupling of the parallel field to the orbital motion arising from the finite layer thickness and the large Fermi wavelength of the quasi-two-dimensional system at low carrier densities.

Control of the magnetic and magnetotransport properties of La0.67Sr0.33MnO3 thin films through epitaxial strain

Abstract: The influence of epitaxial strain, in the form of tetragonal distortions, on the magnetic and magnetotransport properties of La{sub 0.67}Sr{sub 0.33}MnO{sub 3} thin films was studied. The tetragonal distortion (c/a ratio) was modulated through the choice of the substrate, ranging from c/a=1.007 on (001)-oriented (LaAlO{sub 3}){sub 0.3}(Sr{sub 2}AlTaO{sub 6}){sub 0.7} substrates to 0.952 on (110)-oriented GdScO{sub 3} substrates. In agreement with previous theoretical predictions, these large values of tensile strain cause the Curie temperature and the saturation magnetization to decrease, alter the temperature dependence of the resistivity and magnetoresistance, and increase the resistivity several orders of magnitude.

Magnetoresistance in Chalcogenide Spinels

Abstract: The consequences of a simple type of exchange interaction between charge carriers in a broad energy band and localized magnetic moments will be discussed for a ferromagnetic semiconductor. The interaction causes (1) a splitting of the energy band into two bands for the different spin directions, (2) spin disorder scattering of the charge carriers. The calculated temperature and field dependence of the magnetoresistance are compared with experimental data of CdCr2Se4. The magnetoresistance of compounds MeCr2S4, Me=Fe, Co, Cd was measured. For n‐type CdCr2S4 and for p‐type FeCr2S4 and p‐type CoCr2S4, the magnetoresistance −Δρ/ρ0 was found to be 0.78, 0.05, and 0.05, respectively, at 12 kOe near Tc, whereas n‐type FeCr2S4 and CoCr2S4 show no effect. The magnetoresistance of the system Fe1−xCdxCr2S4 was also measured. The temperature dependence of the polar magneto‐optical Kerr effect of CdCr2Se4 is discussed in connection with the described model for the energy bands.

Colossal Magnetoresistance in a Rare Earth Zintl Compound with a New Structure Type: EuIn2P2

Abstract: Single crystals of a new Zintl compound, EuIn2P2, were grown from indium metal as a flux solvent. The compound crystallizes in the hexagonal P6(3)/mmc space group with a unit cell of a = 4.0829(6) A, c = 17.595(4) A, and Z = 2. It contains alternating Eu2+ layers and [In2P2]2- layers. This compound is paramagnetic at high temperatures with a magnetic transition at 24 K. In the magnetically ordered state, it shows large magnetic anisotropy. The temperature-dependent resistivity of this compound suggests interaction between conduction electrons and local spins. Negative colossal magnetoresistance of up to −398% (MR = {[ρ(H) − ρ(0)]/ρ(H)} × 100%) at 5 T is observed at 24 K.