We propose novel approaches to investigate exotic spin-dependent interactions, $V_{4+5}$ and $V_{12+13}$, between polarized electrons and unpolarized nucleons. A rotating torsion balance is used as the detection apparatus. The pendulum serves as the source of polarized electrons. It comprises a cubic samarium cobalt (${\mathrm{SmCo}}_5$) magnet surrounded by six iron (Fe) pieces, providing approximately $1\times {10}^{23}$ polarized electrons. Tungsten nucleon sources are symmetrically positioned on both sides of the pendulum. $V_{4+5}$ is detected by rotating the nucleon sources about the horizontal axis, while $V_{12+13}$ is detected by rotating them about the vertical axis. After a comprehensive evaluation of random noise and systematic effects, the sensitivity for detecting external torques can reach $1.2\times {10}^{-18}\mathrm{N}·\mathrm{m}$. This sensitivity enables new constraints on the coupling parameters $f_{4+5}^{en}$ and $f_{12+13}^{en}$ for interaction ranges from 0.1 to $10\mathrm{\mu }\mathrm{eV}$. These constraints are expected to improve previous limits by factors of 4 and 170, respectively.

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• Hypothetical particle physics models
• Hypothetical gauge bosons