Large‐Size Bulk and Thin‐Film Stilbazolium‐Salt Single Crystals for Nonlinear Optics and THz Generation

Abstract

We present new stilbazolium salt DSTMS (4‐N,N‐dimethylamino‐4′‐N′‐methyl‐stilbazolium 2,4,6‐trimethylbenzenesulfonate) with both high second‐order nonlinear optical properties and very favorable crystal growth characteristics. We are able to obtain very large area bulk single crystals of more than 3 × 3 × 0.2 cm3 with a high optical quality without using seed crystals by using low‐temperature solution growth. We also demonstrate the growth of single crystalline thin films of DSTMS with an area of up to 6 × 5 mm2 and a thickness between 5–30 μm. Nonlinear optical measurements reveal that DSTMS possesses large nonlinear optical susceptibilities with χ111(2) = (430 ± 40) pm V–1 at 1.9 μm. Highly efficient generation of broadband THz waves with THz electric field strengths of more than 4 kV cm–1 using 160 fs laser pump pulses at a wavelength λ = 1.45 μm and DSTMS crystals has been demonstrated.

Mode-locking and frequency mixing at THz pulse repetition rates in a sampled-grating DBR mode-locked laser

“…The regrowth-free approach enables Al-containing epitaxial layers to be used, as there is no exposure of surfaces containing Al, which can oxidize and cause problems during epitaxial regrowth [6]. The results presented in this article suggest that our device could be used as a compact, stable, solid-state practical laser source for generating THz radiation using a photoconductive antenna [7] or nonlinear optical crystal [8].…”

Molecular Structures and Second-Order Nonlinear Optical Properties of Ionic Organic Crystal Materials

“…Yang et al investigated new stilbazolium salts which were grouped into three series with various kinds of counter anions [39]. Comparison of the experimental results ( Figure 3) revealed that introducing especially long counter anions into stilbazolium derivatives does not only restrain the SHG activity but also influences the growth of single crystals.…”

“…Thus ionic π-conjugated species can be highly polarized when an appropriate substituent is introduced into the cation parts. Therefore, numerous studies on modifying the cation of stilbazolium compounds have been carried out and some interesting achievements have been attained [37][38][39]. As shown in Figure 4, the cation of DAST could be divided into five parts (A-E).…”

Combining THz laser excitation with resonant soft X-ray scattering at the Linac Coherent Light Source

“…We use a nonlinear organic crystal, 4-N, N-dimethylamino -4 -N-methyl-stilbazolium 2,4,6-trimethylbenzenesulfonate (DSTMS), as a medium for nonlinear frequency conversion (Yang et al, 2007). Strong THz pulses are achieved via optical rectification of mJ-level pulses centered around 1.5 mm in wavelength (Hauri et al, 2011).…”