Spin wave mediated quantum corrections in epitaxial antiferromagnetic Cr 2 Al films

Although quantum corrections (e.g., weak localization and electron-electron interaction) due to disorder, coherence, and interactions have been intensively studied for decades, understanding the magnon-electron interaction effect on quantum transport properties in magnetic systems still remains a challenge. Thus, the role of spin waves in the quantum transport of magnetic materials has not yet been fully understood. Driven by the miniaturization of spintronics devices possibly moving forward to quantum transport dimensions, in this work, we investigate spin wave mediated quantum transport in epitaxial antiferromagnetic ${\mathrm{Cr}}₂\mathrm{Al}$ films. Temperature($T$)-dependent conductance measurements reveal an additional linear $T$ contribution in the low-temperature range ($T<$ 30 K), which can be ascribed to the spin wave mediated electron-electron interactions in antiferromagnets. Brillouin light scattering confirms an antiferromagnetic resonance at near 80 GHz, consistent with the spin-flop field ${H}_{\mathrm{SF}}\ensuremath{\sim}$ 30 kOe derived from magnetoresistance measurements. Furthermore, the anomalous Hall effect in 2 nm ${\mathrm{Cr}}₂\mathrm{Al}$ films exhibits ${G}_{\mathrm{AH}}\ensuremath{\propto}$ ln $T$ and ${G}_{\mathrm{AH}}\phantom{\rule{4pt}{0ex}}\ensuremath{\propto}\phantom{\rule{4pt}{0ex}}{G}_xx^0.9$ ($T<$ 100 K), indicating that electron-electron Coulomb interactions contribute to the anomalous Hall effect through the extrinsic skew scattering mechanism, while the spin wave mediated electron-electron interactions show no contribution. These results provide critical insights into the effect of spin waves on the quantum transport properties of magnetic materials.