Theory of Kerr instability amplification

Evolution of lasers in Kerr nonlinear materials is inextricably linked with unstable behavior. Current research has investigated the growth of optical Kerr instability out of noise, which results in phenomena such as conical emission and filamentation in bulk materials, and modulation instability in optical fibers. Here, we suggest that seeding Kerr instability in dielectrics can be used for wideband optical amplification ranging from the second harmonic of the pump laser to the mid-infrared. Our theoretical feasibility analysis focuses on the infrared. We find that one- to two-cycle pulse amplification by 3–4 orders of magnitude in the wavelength range of 1–14 μm is feasible with currently available laser sources. Final output energies in the range of a few tens of μJ are achievable corresponding to about 0.25% of the pump energy. Such intense ultrashort mid-infrared radiation sources will substantially impact research in nonlinear spectroscopy, strong-field physics, attosecond science, and ultrafast laser electron accelerators.