Mikhail Erekhinsky

Publications (5)3.84 Total impact

• Article: Temperature dependence of in-plane correlation lengths in exchange biased Co/FeF2

  X. Lu, S. Roy, E. Blackburn, Mikhail Erekhinsky, Ivan K. Schuller, J. B. Kortright, S. K. Sinha
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  ABSTRACT: We have measured resonant soft x-ray diffuse magnetic scattering as a function of temperature in a positively exchange biased Co/FeF2 bilayer and analyzed the data in the distorted wave Born approximation to obtain in-plane charge and magnetic correlation lengths associated with the Co and FeF2 layers and estimate interfacial roughness. Tuning to the Fe and Co L3 edges reveals significantly different temperature trends in these quantities in the antiferromagnetic and ferromagnetic layers, respectively. While the magnetic correlation length of the uncompensated interfacial spins in FeF2 layer increase as temperature decreases, these quantities remain unchanged in the Co layer. Our results indicate that uncompensated Fe spins order within a range of few hundred nanometers in otherwise randomly distributed uncompensated magnetic moments, giving rise to spin clusters in the antiferromagnet whose size increase as the temperature decrease.
  03/2012;
• Article: Surface enhanced spin-flip scattering in lateral spin valves

  Mikhail Erekhinsky, Amos Sharoni, Fèlix Casanova, Ivan K. Schuller
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  ABSTRACT: Nonlocal transport in Py/Cu lateral spin valves shows that the Cu spin diffusion length and the apparent Py spin polarization increase with Cu thickness. A proper quantitative analysis shows that the Cu spin diffusion length is dominated by surface spin-flip scattering and that the Py and Cu thickness dependence of spin polarization is due to strong spin-flip back-scattering at the Py/Cu interface. This solves a long-standing puzzle regarding the discrepancy in Py spin polarizations obtained from different measurements. Interestingly, the Cu surface oxidation causes enhanced spin diffusion, contrary to expectations. These surface effects substantially affect the performance of lateral spin valves.
  Applied Physics Letters 01/2010; 96(2):022513-022513-3. · 3.84 Impact Factor
• Source

  Available from: ArXiv

  Article: Enhanced spin-flip scattering at the surface of copper in lateral spin valves

  Mikhail Erekhinsky, Amos Sharoni, Felix Casanova, Ivan K. Schuller
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  ABSTRACT: We performed non-local electrical measurements of a series of Py/Cu lateral spin valve devices with different Cu thicknesses. We show that both the spin diffusion length of Cu and the apparent spin polarization of Py increase with Cu thickness. By fitting the results to a modified spin-diffusion model, we show that the spin diffusion length of Cu is dominated by spin-flip scattering at the surface. In addition, the dependence of spin polarization of Py on Cu thickness is due to a strong spin-flip scattering at the Py/Cu interface.
  08/2009;
• Source

  Available from: ArXiv

  Article: Control of spin injection by direct current in lateral spin valves

  Fèlix Casanova, Amos Sharoni, Mikhail Erekhinsky, Ivan K. Schuller
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  ABSTRACT: The spin injection and accumulation in metallic lateral spin valves with transparent interfaces is studied using d.c. injection current. Unlike a.c.-based techniques, this allows investigating the effects of the direction and magnitude of the injected current. We find that the spin accumulation is reversed by changing the direction of the injected current, whereas its magnitude does not change. The injection mechanism for both current directions is thus perfectly symmetric, leading to the same spin injection efficiency for both spin types. This result is accounted for by a spin-dependent diffusion model. Joule heating increases considerably the local temperature in the spin valves when high current densities are injected ($\sim$80--105 K for 1--2$\times10^{7}$A cm$^{-2}$), strongly affecting the spin accumulation. Comment: 6 pages, 5 figures
  10/2008;
• Article: Reduced spin injection at high DC current in lateral spin valves

  Mikhail Erekhinsky, Amos Sharoni, Felix Casanova, Ivan K. Schuller
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  ABSTRACT: We report on non-local transport measurements in all metal lateral spin-valves with transparent contacts. We use direct current to investigate the symmetry in the injection process between a ferromagnet (FM) and a normal metal (NM). At high currents (around 1-2x10^7A/cm^2) the non-local spin valve (NLSV) signal becomes larger when electrons are injected from the FM into the NM. A systematic study of the NLSV signal for different device lengths as a function of current magnitude and direction reveals the origin of this asymmetry. By fitting the near-exponential decay of the signal with distance the effects of FM polarization and NM spin diffusion length can be separated. These results show that the spin diffusion length of the NM is independent of current direction. However, the effective spin polarization of the FM appears to be larger when electrons are injected from FM into NM and smaller when electrons move in opposite direction. Possible explanations for this behavior will be discussed.