in the toroidal geometry*

We bring together high magnetic field techniques, optical spectroscopy, and first principles electronic structure calculations to reveal high-energy, broadband nonreciprocal directional dichroism in Ni₃TeO₆. We focus on the toroidal geometry where polarization is perpendicular to the chiral spin arrangement, and light is propagating orthogonal to both. We employ circularly polarized as well as unpolarized light to fully explore the symmetry properties and eigenstates of the system as well as potential for photonics applications. Due to the spectral range of our work, we demonstrate nonreciprocal effects in the Ni²⁺ d-to-d on-site excitations as well as the phonon side bands that appear on the leading edge of these structures. In addition to being a peculiar and fundamental light-matter interaction in low-symmetric crystals, nonreciprocal directional dichroism can support one-way transparency, optical rectifiers, and high fidelity holograms – just to name a few.