1. Quantum Design Concept
The high harmonic generation process driven by mid-infrared lasers can be used to generate keV energy photons, implementing a >5000 order nonlinear process, while still maintaining the full phase matching that is necessary for good conversion efficiency. This concept represents the most extreme, fully coherent upconversion for electromagnetic waves in the 50 year history of nonlinear optics. Interestingly, the limits of this ultrahigh harmonic geenration are still not understood – neither theoretically or experimentally. It may be possible to generate coherent hard X-rays using a relatively small scale apparatus.
PHASE MATCHED MID-IR DRIVEN HARMONICS:
– Broadband X-ray supercontinuum >keV photon energy
– Automatically isolated attosecond pulse + large chirp
– Balance neutral & plasma indices
T. Popmintchev et al., US Patent 2008/2013.
T. Popmintchev et al., Science 336, 1287 (2012).