An experimentally feasible scheme based on fast magnetic field rotations to generate nuclear polariton entanglement in a 57FeBO3 sample is investigated theoretically. Using a nuclear forward scattering setup with hard x-ray synchrotron radiation, a normal incidence x-ray mirror and two fast rotations of the hyperfine magnetic field in the sample, a nuclear polariton with two counterpropagating branches can produced. These branches are entangled by a single photon. The first magnetic field rotation suppresses nuclear decay, providing a sub-ångström-wavelength standing wave nuclear excitation pattern that could be used to dynamically probe the sample’s atomic structure. By releasing the photon with a second rotation, one additionally obtains robust single-photon entanglement of two simultaneously emitted, spatially separated field modes