Ultrafast spin dynamics and critical behavior in half - metallic ferromagnet : Sr 2 FeMoO
نویسندگان
چکیده
Ultrafast spin dynamics in ferromagnetic half-metallic compound Sr 2 FeMoO 6 is investigated by pump-probe measurements of magneto-optical Kerr effect. Anomalous thermal insulation between spins and electrons due to half-metallic nature of this material gives rise to a very slow spin relaxation from a few to several-hundred picosecond after the optical excitation. The optically detected magnetization dynamics clearly shows the crossover from microscopic photoinduced demagnetization to macroscopic critical behavior with universal power law divergence of relaxation time for wide dynamical critical region.
منابع مشابه
Ultrafast spin dynamics and critical behavior in half-metallic ferromagnet: Sr2FeMoO6
Ultrafast spin dynamics in ferromagnetic half-metallic compound Sr2FeMoO6 is investigated by pump-probe measurements of the magneto-optical Kerr effect. The half-metallic nature of this material gives rise to anomalous thermal insulation between spins and electrons and allows us to pursue the spin dynamics from a few to several hundred picoseconds after the optical excitation. The optically det...
متن کاملSpin polarized tunneling in the half-metallic ferromagnet La0.7Sr0.3MnO3: experiment and theory
The magnetoresistance (MR) in polycrystalline colossal magnetoresistive compounds follows a behavior different from single crystals below the ferromagnetic transition temperature. This difference is usually attributed to spin polarized tunneling at the grain boundaries of the polycrystalline sample. Here we derive a theoretical expression for the contribution of spin polarized tunneling to the ...
متن کاملUltrafast non-local spin dynamics in metallic bi- layers by linear and non-linear magneto-optics
We make a step towards the understanding of spin dynamics induced by spin-polarized hot carriers in metals. Exciting the Fe layer of Au/Fe/MgO(001) structures with femtosecond laser pulses, we demonstrate the ultrafast spin transport from Fe into Au using time-resolved MOKE and mSHG for depthsensitive detection of the transient magnetization. Ultrafast spin dynamics is the key for development o...
متن کاملDetermination of the spin polarization of half-metallic CrO(2) by point contact Andreev reflection.
Andreev reflection at a Pb/CrO(2) point contact has been used to determine the spin polarization of single-crystal CrO(2) films made by chemical vapor deposition. The spin polarization is found to be 0.96 +/- 0.01, which confirms that CrO(2) is a half-metallic ferromagnet, as theoretically predicted.
متن کاملGrowth evolution of laser-ablated Sr(2)FeMoO(6) nanostructured films: Effects of substrate-induced strain on the surface morphology and film quality.
Pulsed laser deposition was used to grow Sr(2)FeMoO(6) films of different thicknesses on MgO(100), SrTiO(3)(100), and LaAlO(3)(100) with respective lattice mismatches of +6.2%, -1.2%, and -4.3%. Surface roughness and morphology, and film crystal quality and epitaxy were determined by atomic force microscopy and x-ray diffraction, respectively. Two-dimensional layer-by-layer growth was evident f...
متن کامل