The effect of circularly polarized light on ESR spectra

Observable shifts in electron spin resonance spectra are predicted to occur as a result of the application of circularly polarized light at a frequency near optical absorption. The shift changes sign with the circularity of the light. In a right circularly polarized beam of intensity 10 W cm−2 and frequency 5 GHz above resonance with the D1 line, propagating in the direction of the magnetic field Bz, the electron spin resonance frequency of atomic sodium is predicted to increase by 4.68 MHz. Measurement of the laser-induced shift would determine the antisymmetric polarizability α′xy = −α′yx of the radical.