The search for supersymmetry is usually confined to the realm of the Large Hadron Collider (LHC). However, scenarios in which the lightest supersymmetric particle is a neutralino with GeV-scale mass are allowed, as long as the squarks are heavy enough to avoid discovery at the LHC. In particular, the neutralino can be produced in B-meson decays thanks to third-generation R-parity-violating (RPV) couplings, which are poorly constrained.

I will describe proposed searches for a light neutralino at the Belle II experiment, utilizing kinematic constraints that arise from the near-threshold production of two B mesons for both missing-energy and displaced-vertex signatures. The proposed searches have the best sensitivity to third-generation RPV couplings. Potential extensions to other scenarios will be briefly discussed as well.