Extreme ultraviolet radiation for coherent diffractive imaging with high spatial resolution

Using different noble gases, argon, neon and helium, we are able to generate by high-harmonic generation (HHG) just a few harmonic orders in the spectral range 10–35 nm with a photon flux of ∼ 2.10 12 photons/(harmonic cm 2 s) for argon and ∼ 10 10 photons/(harmonic cm 2 s) for helium. The few-harmonic-order radiation is used for coherent diffractive imaging directly without any spectral filter. A spatial resolution of ∼ 100 nm is achieved using a ∼ 30 nm HHG source.