X-Ray Laser




Rapidly emerging just an year after the invention of the laser in 1960, nonlinear optics revolutionized the ability to create directed, laser-like beams particularly in the regions of the electromagnetic spectrum where lasers based on conventional concepts are not practical. New breakthroughs in extreme nonlinear optics promise a similar revolution in the X-ray regime. The X-ray wavelengths are about 1000 times shorter than those of visible rays, and range between the wavelengths of the longer-wavelength UV rays and the shorter-wavelength gamma rays:

Soft X-rays: 10 nm – 0.1 nm/100 eV – 10 keV.
Hard X-rays: 0.1 nm – 0.01 nm/10 keV – 100 keV.

The team in our quantum-design X-ray labs is investigating the fundamental atomic limits of the extreme nonlinear optical process of high harmonic generation, and its phase matching and group velocity matching limits in the soft and hard X-ray regime within the scope of the 3 most promising, complementary concepts:
1) Mid-infrared laser driven upconversion
2) UV laser driven upconversion
3) Frequency and angular momentum mixing of driving lasers in extreme nonlinear optics

Some of the main research goals of the group are to produce bright coherent X-ray light from laboratory-scale systems, at photon energies of 1-10 keV and greater with unprecedented attosecond-to-zeptosecond pulse durations, and with arbitrary spectral, spatial, temporal shape, and spin and orbital angular momentum.


T. Popmintchev et al., US Patent 2008/2013.
T. Popmintchev et al., Science 336, 1287 (2012).
T. Popmintchev et al., US Patent 2013/2015.
D. Popmintchev et al., Science 350, 1125 (2015).
T. Fan, et al., CLEO Postdeadline (2015).
T. Fan, et al., PNAS 112, 46, 14206 (2015).