Ultrafast Imaging Below the Diffraction Limit with High Harmonic Deactivation Microscopy

Nonlinear optical microscopy provides elegant means for label-free imaging of biological samples and condensed matter systems. The wide-spread areas of application could even be increased if resolution was improved, which the famous Abbe diffraction limit now restrains. Super-resolution techniques can break the diffraction limit, but most rely on fluorescent labeling. This makes them incompatible with (sub-)femtosecond temporal resolution and applications that demand the absence of labeling. In a recent study, we introduced harmonic deactivation microscopy (HADES) for breaking the diffraction limit in nonfluorescent samples [1].