Broadband sum-frequency generation of spectrally incoherent pulses

Abstract

We study and demonstrate the nonlinear frequency conversion of broadband optical pulses from 1053 nm to 351 nm using sum-frequency generation with a narrowband pulse at 526.5 nm. The combination of angular dispersion and noncollinearity cancels out the wave-vector mismatch and its frequency derivative, yielding an order-of-magnitude increase in spectral acceptance compared to conventional tripling. This scheme can support the nonlinear frequency conversion of broadband spectrally incoherent nanosecond pulses generated by high-energy lasers and optical parametric amplifiers to mitigate laser−plasma instabilities occurring during interaction with a target. The experimental results obtained with KDP crystals are in excellent agreement with modeling, demonstrating the generation of spectrally incoherent pulses with a bandwidth larger than 10 THz at 351 nm.

Effect of THz-bandwidth incoherent laser radiation on bulk damage in potassium dihydrogen phosphate crystals

“…They are combined with a 527-nm narrowband beam for broadband sum-frequency generation to produce a UV pulse having a spectrum with peaks centered at 348 nm and 354 nm. Further information on this system can be found in 9 . Figure 1 shows a measured UV pulse shape and spectrum representative of test conditions.…”

Spectral-temporal Measurement Capabilities of Third-order Correlators

“…shown in figure 1(a), and the efficiency given by the wavevector mismatch, shown in figure 1(b), can be generated [28]. The resulting spectral efficiency map is shown in figure 1 The combination of fundamental and second-harmonic spectra is generating a two-dimensional spectral intensity profile (see figure 1a).…”

Polychromatic drivers for inertial fusion energy

“…The amplification and frequency-conversion processes of the 1047 nm and 1059 nm lasers using deuterated potassium dihydrogen phosphate (DKDP) are presented as examples in figures 3(a) and (b), where the refractive index, walk-off angle and effective nonlinear coefficient of DKDP crystal are obtained from Sellmeier equations and second-order nonlinear optical tensor [55,58]. Note that DKDP is one of the optimal nonlinear crystals currently used in the high-power laser systems due to its high optical quality for kilojoule pulses [39]. Meanwhile, DKDP is also used in the generation of low-coherent green laser at the energy scale of kilojoule owning to its broadband nature [62].…”