Ultra-supercontinuum generation with high intense femtosecond pulses

Extreme spectral broadening has been theoretically simulated from the index of refraction changes from the envelope response to the fifth- and third-order susceptibilities from self-phase modulation (SPM) under the influence of an extremely high-intensity femtosecond laser pulse to potentially produce spectral broadening changes extending from extreme X-rays, UV, visible, THz down to DC. The theoretical results show that an extremely high-intensity pulse as high as on the order of 10(14)similar to 10(16) W/m(2) can influence the fourth-order refractive index arising from fifth-order susceptibility large enough that the nonlinear n(4)I(0)(2) term to overtakes the n(2)I(0)(2) term from the third-order susceptibility to produce the ultra-supercontinuum broadening in the liquids such as CS2 and rare gas liquids and solids such as calcite, ZnO, Si, Argon, and Krypton. There has been experimental verification at lower intensities that the SC is symmetrical in frequency about laser frequency for say a Gaussian pulse extends from, UV visible, NIR, to MIR by many researchers using various states of matter. This paper provides an opportunity to extend the SPM model from X-rays to DC to form Ultra Supercontinuum Generation (USCG) using extreme intensity fs pulses in the four states of matter: gases, liquids, solids, and plasmas. At the highest intensity, a continuum with weaker intensity goes towards the X-ray region on the anti-Stokes side.

Automated summary

Theoretical simulations have shown that extreme spectral broadening can be achieved through self-phase modulation with high-intensity femtosecond laser pulses, extending from X-rays to DC. Experimental verification has demonstrated symmetrical spectral properties around the laser frequency in various states of matter. This research offers the opportunity to further explore ultra-supercontinuum generation using extreme intensity femtosecond pulses.