Giant Anisotropic Spin Absorption in Chiral Hybrid Semiconductors

ABSTRACT Control of spin‐current absorption in non‐magnetic materials is central to realizing spin‐current switches and low‐power spintronic technologies, yet anisotropic responses have so far been limited to a narrow class of crystalline materials. Here we demonstrate giant chirality‐induced anisotropic spin‐current absorption (CASA) in solution‐processed chiral hybrid organic–inorganic semiconductors (HOISs), establishing them as a versatile platform for symmetry‐selective spin manipulation. Zero‐dimensional [ R/S/rac ‐MBA] 4 Bi 2 Cl 10 (MBA = α ‐methylbenzylammonium) HOISs exhibit more than an order‐of‐magnitude variation in spin absorption between orthogonal spin polarizations. Strikingly, despite the lack of chiroptical activity, racemic films exhibit a similarly strong spin anisotropy, indicating that global crystallographic chirality is not a prerequisite for CASA. Structural chirality analysis reveals that the CASA is governed by the orientation of local chiral axes associated with the organic cations in HOISs. These results establish molecular chirality as an active design parameter for manipulating spin transport, positioning HOISs as a broadly compelling platform for spin‐based functionalities.