Dynamic imaging of an antiferromagnetic domain wall via quantum-impurity relaxometry

While spin textures in materials exhibiting zero net magnetization, such as antiferromagnetic domain walls (DWs), have attracted much interest lately due to their robustness against external magnetic noise, their generic detection via conventional magnetometry remains a challenging task. Here, we propose quantum relaxometry as a new route to image spin textures by probing the collective spin modes harbored by them. We investigate the Goldstone modes hosted by an antiferromagnetic domain wall and assess the relaxation rate of a quantum-spin sensor interacting with them. We show that such modes can be detected via relaxometry in some common antiferromagnets. Moreover, based on symmetry considerations, we propose a simple protocol to probe the individual dynamics of each mode.