Non-resonant field enhancement in an isotropic non-linear medium

We want to probe non-resonant field enhancement by monitoring third-harmonic generation in a noble gas. This is done under the condition that neither the fundamental wave nor the third harmonic is resonant to any level of the atomic species. A potential field-enhancement is attributed to an imbalance between ingoing and outgoing dipole waves induced by the non-linear wave mixing. To generate the dipole waves, the fundamental wave is focused by a parabolic mirror. The project comprises work on the experimental setup as well as the assessment of possible field-enhancement indicators.