Unconventional one-magnon scattering resistivity in half metals

TL;DR

This paper reveals that unconventional one-magnon scattering significantly influences low-temperature resistivity in half-metals, especially when considering non-rigid-band effects, providing a new way to identify half-metallic materials.

Contribution

It demonstrates that non-rigid-band behavior leads to a T^3 resistivity dependence due to one-magnon scattering in half-metals, challenging previous assumptions.

Findings

Unconventional one-magnon scattering causes T^3 resistivity dependence.

Comparison with La_1-x Sr_x MnO_3 supports the theory.

Provides a new test for identifying half-metallic materials.

Abstract

Low-temperature resistivity of half-metals is investigated. To date it has been discussed that the one-magnon scattering process in half-metals is irrelevant for low-temperature resistivity, due to the fully spin-polarized electronic structure at the ground state. If one takes into account the non-rigid-band behavior of the minority band due to spin fluctuations at finite temperatures, however, the unconventional one-magnon scattering process is shown to be most relevant and gives T^3 dependence in resistivity. This behavior may be used as a crucial test in the search for half-metallic materials which are potentially important for applications. Comparison with resistivity data of La_1-x Sr_x MnO_3 as candidates for half-metals shows good agreement.