Spin-wave-induced correction to the conductivity of ferromagnets

Abstract

We calculate the correction to the conductivity of a disordered ferromagnetic metal due to spinwave-mediated electron-electron interactions. This correction is the generalization of the AltshulerAronov correction to spin-wave-mediated interactions. We derive a general expression for the conductivity correction to lowest order in the spin-wave-mediated interaction and for the limit that the exchange splitting ∆ is much smaller than the Fermi energy. For a "clean" ferromagnet with ∆τ el /h 1, with τ el the mean time for impurity scattering, we find a correction δσ ∝ −T 5/2 at temperatures T above the spin wave gap. In the opposite, "dirty" limit, ∆τ el /h 1, the correction is a non-monotonous function of temperature.

Quantum corrections to the conductivity of itinerant antiferromagnets

“…] We note here that in their theoretical evaluations, Ref. [15] did not obtain a linear T dependence in any regime of a ferromagnet. The difference seems to appear from the choice of the cutoff q c ≡ √ T /A 2 , using α = 2 for ferromagnets.…”

“…As pointed out in Ref. [15], the large disorder limit considered here allows us to ignore additional nondiffuson diagrams considered there.…”

“…While Ref. [15] assumes the upper cutoff for the q integral to be q c , we take the upper limit to be given by q 0 = 1/l, with q c 1/l such that the major contribution of the q integral comes from q 0 > q > q c . In this case,…”

“…However, while phase-breaking lengths and corrections to conductivity for ferromagnets have been studied before [9,13,15], and some results for antiferromagnetic films have been reported while explaining experimental observations [14], a systematic study of the antiferromagnetic systems is still missing. In this work, we provide some details of results used in Ref.…”