Ultraviolet-light generation in nitrogen-doped silica fiber

Abstract

Nonlinear light transformations were observed in a nitrogen-doped silica fiber pumped with a Nd:YAG laser (lambda=1.06 microm) . Light generation in the spectral range 355-430nm was obtained with an efficiency of up to 2x10(-4) . The UV light was found to be the result of third-harmonic generation, stimulated Raman scattering of the third harmonic, and third-harmonic generation from the Stokes components of the pump light. Lasing based on the color centers of nitrogen-doped silica was observed in the range 380-430nm.

Blue cooperative upconversion in Yb3+-doped multicomponent sol-gel-processed silica glass for three-dimensional display

“…Another important point to be considered here is that the blue light can be generated in silica-based glasses via third-harmonic generation ͑THG͒. 15 However, third-order nonlinear processes such as THG require high intensity pulse excitation. In our case, the cooperative blue emission of Yb 3ϩ was observed using a cw excitation source, which is more suitable for compact devices.…”

Ultra-violet generation by third-harmonic conversion in conventional solid-core fibers

“…Noted that a similar feature has been observed in ref. [6] [9]. In these previous studies, they have explained that these sub peaks corresponded to the sum frequency components among the pump and the first and second Stokes of the SRS.…”

“…The result shows that there are several discrete conditions where the phase mismatching can be reduced to be less than 1% for the fundamental (pump) wave in the region of 1020-1410nm (i.e., THG at 310-470 nm). In this way, the PMC is not satisfied perfectly, however, the phase mismatching can be reduced by using the difference between the propagation constants of fundamental and higher-order guided modes [1] [9].…”

“…Among these applications, the third-harmonic generation (THG) by using silica-based optical fibers had been studied extensively during the '80s and '90s because of its potential applications to the compact green, blue and ultraviolet (UV) sources [2]- [9]. For example, in refs.…”

“…However, since the conversion efficiency was too low due to the phase mismatching between fundamental and third-harmonic waves, they needed to launch the extremely intense optical power to observe THG. Thus, in these previous experiments, they have used Q-switched and mode-locked Nd:YAG lasers, which generated burst picosecond pulse train with Q-switch envelope [2]- [6] [9]. (In this way, the continuous operation was not straightforward.)…”