Polarization- and Frequency-Resolved Photocurrents as a Symmetry Probe in Quantum Materials

Understanding and controlling symmetry and band geometry in quantum materials is central to next-generation optoelectronics. We present polarization- and photon-energy-resolved photocurrent measurements that exhibit symmetry-sensitive responses in a chiral cubic material. The data are analyzed using group theory approach along with the first-principles calculations . Our measurements show an unexpected response inconsistent with the underlying symmetry of the material. We propose a general framework that explains the origin of these unexpected responses by revealing a hidden broken symmetry. Our results outline a general diagnostic platform that links nonlinear photo-response to underlying crystal symmetry and band geometry, informing materials design and device-relevant functionalities.