Contactless Detection of Giant Helicity-Dependent Photovoltage in Chiral 2D Perovskites.

Chiral-induced spin selectivity (CISS) provides a direct route for spin filtering without magnetic fields, yet directly probing spin-dependent charge separation in low-dimensional hybrid perovskite systems remains elusive. Here, we systematically investigate helicity-dependent charge-carrier separation in chiral 2D perovskites using a novel contactless approach that employs a dynamic long-range organization strategy to enhance the chiroptical response. By employing contactless circularly polarized time-resolved surface photovoltage (CP-TRSPV), we directly monitor the interplay between chirality and charge separation dynamics across multiple timescales. While typical chiro-optical absorption in these materials is minimal, we observe a giant photovoltage anisotropy factor gSPV of -0.7 and 0.17 for the R- and S-enantiomers, respectively. This significant anisotropy, persisting from nanoseconds to milliseconds, indicates that the response is not merely a surface optical effect and is consistent with CISS-associated spin-polarized transport. The successful contactless demonstration of giant helicity-dependent photovoltage substantially expands our understanding of chirality-controlled charge dynamics and their application in spin-optoelectronic devices.