Evidence for Magnon-Assisted Exciton Radiation in a Layered Antiferromagnetic Semiconductor
Phys. Rev. Lett. 137, 136701 – Published 21 September, 2026
DOI: https://doi.org/10.1103/4c9s-gslh
Abstract
Layered van der Waals (vdW) magnetic semiconductors open a new avenue for exploring intertwined excitonic and magnetic phenomena. Here, we investigate this interplay in the vdW antiferromagnet , uncovering an exceptionally long exciton lifetime () below the Néel temperature (). We demonstrate that the exciton lifetime is primarily governed by phonon-assisted nonradiative recombination and thus exhibits a strong temperature dependence. In contrast, the exciton radiative recombination shows a distinct temperature dependence that is sensitive to magnetic order. Below , the temperature dependence of the radiative recombination rate is consistent with a magnon-assisted emission pathway, while above it reflects the combined effects of short-range spin correlations and phonons. These findings not only establish as a compelling candidate for excitonic devices due to its long lifetime and correlation with magnetic orders but also provide crucial insights into the interplay between excitons, spins, and lattices in vdW magnetic semiconductors.