Bulk photovoltaic effect in antiferromagnet: Role of collective spin dynamics

Inspired by recent advancements in the bulk photovoltaic effect which can extend beyond the independent-particle approximation (IPA), this study delves into the influence of collective spin dynamics in an antiferromagnet on photocurrent generation using a time domain calculation. In the linear and photocurrent conductivity spectra, we observe peaks below the band gap regime, attributed to the resonant contributions of collective modes, alongside broadband modifications resulting from off-resonant spin dynamics. Notably, the emergence of spin dynamics allows various types of photocurrent, which are absent in the IPA framework. Furthermore, we emphasize the importance of energy scale proximity between electronic and spin degrees of freedom in enabling efficient feedback. These findings offer new avenues for efficient energy harvesting and optoelectronic applications.