Torsion-induced optical rotation in isotropic glass media.

We have revealed that torsion stresses produce an optical activity effect in initially isotropic glass media. The optical activity caused by spatially inhomogeneous mechanical stresses has been experimentally studied for a standard glass BK7 subjected to torques, using a single-beam polarimetry and a polarizer-sample-analyzer scheme. The torsion-gyration coefficient for the BK7 glass has been determined as (3.96±0.82)×10  m/N.