Optical detection of transition metal ion electron paramagnetic resonance by coherent Raman spectroscopy

Coherent Raman scattering in combination with optical heterodyne detection provides an attractive new technique for the measurement of electron paramagnetic resonance (EPR). The technique is applicable to both electronic ground and excited states. In contrast to conventional ODMR techniques, it monitors the precessing magnetisation and produces phase-sensitive spectra. We have demonstrated the feasibility of the experiment using the 4A2 to 4E(4T2) transition of Cr3+ in Al2O3 (ruby).