Ground state electronic structure calculations of the multiple spin density wave state in g-Fe

Kakehashi Y., O. Jepsen, N. Kimura

Hokkaido Institute of Technology, Maeda, Teine-ku, Sapporo 006, Japan
Max-Planck-Institut für Festkörperforschung, 70569 Stuttgart, Germany 

The electronic structure calculations of noncollinear multiple spin density wave (MSDW) state in g-Fe, which was found in a recent molecular-dynamics calculation, have been performed on the basis of the first-principles tight-binding LMTO (linear muffin-tin orbital) method and the GGA (generalized gradient approximation) potential.  The calculated MSDW state is shown to be dominated by the 3-Q waves with the wave number Q = 0.6 in unit of 2p/a, a being the fcc lattice constant.  The secondary waves are created so as to suppress the amplitude fluctuations of local magnetic moments.  It is found that the energy of the MSDW state is lower than that of the single-Q helical state with Q = 0.6 at any volume due to the dip of the density of states at the Fermi level.  From the energy comparison of various magnetic structures, it is concluded that the MSDW may be stabilized in the region 6.8 < a < 7.0 a.u., while the MSDW characterized by Q = 1.0 seems to be stabilized below a = 6.8 a.u.

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