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arXiv · 0908.3342

Anomalous Pinning Fields in Helical Magnets: Screening of the Quasiparticle Interaction

T. R. Kirkpatrick·D. Belitz
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Abstract

The spin-orbit interaction strength g_so in helical magnets determines both the pitch wave number q and the critical field H_c1 where the helix aligns with an external magnetic field. Within a standard Landau-Ginzburg-Wilson (LGW) theory, a determination of g_so in MnSi and FeGe from these two observables yields values that differ by a factor of 20. This discrepancy is remedied by considering the fermionic theory underlying the LGW theory, and in particular the effects of screening on the effective electron-electron interaction that results from an exchange of helical fluctuations.

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T. R. Kirkpatrick, D. Belitz. 2009-09-10. Anomalous Pinning Fields in Helical Magnets: Screening of the Quasiparticle Interaction. https://doi.org/10.1103/physrevb.80.220401

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