High-Efficiency Generation of 0.12 mJ, 8.6 Fs Pulses at 400nm Based on Spectral Broadening in Solid Thin Plates

Abstract

We demonstrate efficient generation of continuous spectrum centered at 400 nm from solid thin plates. By frequency doubling of 0.8 mJ, 30 fs Ti:sapphire laser pulses with a BBO crystal, 0.2 mJ, 33 fs laser pulses at 400 nm are generated. Focusing the 400-nm pulses into 7 thin fused silica plates, we obtain 0.15 mJ continuous spectrum covering 350–450 nm. After compressing by 3 pairs of chirped mirrors, 0.12 mJ, 8.6 fs pulses are achieved. To the best of our knowledge, this is the first time that sub-10-fs pulses centered at 400 nm are generated by solid thin plates, which shows that spectral broadening in solid-state materials works not only at 800 nm but also at different wavelengths.

Generation of Intense Sub-10 fs Pulses at 385nm*

“…Although the pulse duration is longer than previously reported UV pulses of 4.4 fs, [8] 7.5 fs [15] and 8 fs, [12,13] the pulse energy in this work is much stronger, which is capable of reaching a peak intensity of 5.3 × 10 15 W/cm 2 by focusing the beam down to 30 µm. The pulse duration can be further shortened by maximizing the SH bandwidth through better NIR spectral shaping, which needs extensive studies on the spectral shape dependence of the HF output pulses upon the dispersion of input pulses.…”

“…Another scheme was to perform the frequency upconversion with long pulses first, then compress the long UV pulses down to sub-10 fs with HF [12] or solid thin plates. [13,14] In spite of higher efficiency, significant satellite pulses existed due to the large high-order dispersion during spectral broadening process. Liu et al [15] eliminated the satellite pulses with a deformable mirror system, but suffered from additional energy loss.…”

Compact and robust supercontinuum generation and post-compression using multiple thin plates

“…Also, the gas-filled waveguide is in general implemented in a vacuum system which adds bulk and complexity to the setup. To overcome these disadvantages, we propose to use the newly developed technique based on multi-plate spectral broadening [34][35][36][37][38][39][40][41][42] . This technique uses several pieces of thin fused silica plates, each with a thickness of a few hundred of micrometers, placed after the focus of the fundamental laser beam to broaden the spectral of the input pulse through SPM while avoiding the breakdown and the spatial distortion in the medium due to self-focusing and conical diffraction [43,44] .…”

Broadband mid-infrared pulse via intra-pulse difference frequency generation based on supercontinuum from multiple thin plates*

“…[20,21] It has been reported in a variety of spectral range coving 400 nm to 3500 nm and pulse energy from the level of hundreds of µJ to a few of mJ. [22][23][24][25][26] The spectrum of the driving laser is broadened by self-phase modulation (SPM), self-steepening, and self-focusing in an ar-ray of strategically positioned thin plates. This multi-plate scheme is applicable with a broad range of input energy in various materials, simultaneously offering transmittance higher than 85%.…”