In the ongoing broad search for dark matter, axions and axionlike particles have attracted considerable attention due to their potential to simultaneously resolve the strong $CP$ problem and serve as viable candidates for cold dark matter. These light bosons can mediate novel spin-dependent forces over macroscopic distance, providing a promising pathway for the indirect detection of dark matter. In this work, we propose an experimental scheme to search for the axion-mediated spin-mass interaction. The setup employs a closed-loop magnetic array to generate a highly spin-polarized electron ensemble and utilizes a gold microsphere probe that serves both as a source of unpolarized nucleons and as a high-sensitivity force sensor, enabling sensitive probing of electron-nucleon interactions at the micrometer scale. By systematically analyzing the spurious forces, we optimize the experimental parameters to maximize the exotic force signal. Based on the preliminary design parameters, with the force sensitivity achievable at low temperature, this experiment is expected to explore a parameter space with a coupling constant smaller than the current stringent constraints from micrometer to millimeter interaction range. The minimum detectable coupling constant is expected to $g_S^N{g}_P^e/\hslash c=9.4\times {10}^{-20}$ at $\lambda =5\mathrm{\mu }\mathrm{m}$. Specifically, the lower bound of the parameter space explored in this study will be an order of magnitude lower than the most stringent existing constraints for axion-mediated spin-mass interactions.

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• Particle interactions
• Axions