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arXiv · 1101.0674

Precursor phenomena at the magnetic ordering of the cubic helimagnet FeGe

H. Wilhelm·M. Baenitz·M. Schmidt·U. K. Roessler·A. A. Leonov·A. N. Bogdanov
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Abstract

We report on detailed magnetic measurements on the cubic helimagnet FeGe in external magnetic fields and temperatures near the onset of long-range magnetic order at $T_C= 278.2(3)$ K. Precursor phenomena display a complex succession of temperature-driven crossovers and phase transitions in the vicinity of $T_C$. The A-phase region, present below $T_C$ and fields $H<0.5$ kOe, is split in several pockets. Relying on a modified phenomenological theory for chiral magnets, the main part of the A-phase could indicate the existence of a $+π$ Skyrmion lattice, the adjacent A$_2$ pocket, however, appears to be related to helicoids propagating in directions perpendicular to the applied field.

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H. Wilhelm, M. Baenitz, M. Schmidt, U. K. Roessler, A. A. Leonov, A. N. Bogdanov. 2011-01-04. Precursor phenomena at the magnetic ordering of the cubic helimagnet FeGe. https://doi.org/10.1103/physrevlett.107.127203

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