High harmonics in Condensed Matter: A review

When solids are exposed to intense laser fields whose forces are comparable to the binding forces of valence electrons in crystals, nonlinear optics of solids advances to the nonperturbative or extreme nonlinear regime. A hallmark effect of extreme nonlinear optics is the emission of high-order harmonics of the laser from the bulk of materials. In a new invited publication for Nature Photonics, Eleftherios Goulielmakis and Thomas Brabec review the recent experimental and theoretical advances in this emerging area of study and highlight the potential future directions and applications. Read online here.