Ultraviolet to mid-infrared gas-filled anti-resonant hollow-core fiber lasers

Abstract

We will present our recent works on fiber lasers enabled by noble and Raman-active gas-filled anti-resonant hollow-core fiber (ARHCF) technology. First, we will present the generation of supercontinuum (SC) spanning from 200 nm to 4 µm based on a Argon (Ar)-filled ARHCF pumped at 2.46 μm wavelength with 100 fs pulses and ~8 μJ pulse energy. Then we will discuss our recent work on stimulated Raman scattering (SRS) effect in a hydrogen (H2)-filled ARHCF, to achieve infrared Raman lasers. By employing the single-stage vibrational SRS effect, a 4.22 μm Raman laser line is directly converted from a linearly polarized 1.53 μm pump laser. A quantum efficiency as high as 74% was achieved, to yield 17.6 µJ pulse energy. The designed 4.22 μm wavelength is overlapped with the strongest CO2 absorption, therefore constituting a promising way for CO2 detection. In addition, we report a multi-wavelength Raman laser based on cascaded rotational SRS effect. Four Raman lines at 1683 nm, 1868 nm, 2099 nm, and 2394 nm are generated, with pulse energies as high as 18.25 µJ, 14.4 µJ, 14.1 µJ, and 8.2 µJ, respectively. The energy of these Raman lines can be controlled by tuning the H2 pressure from 1 bar to 20 bar.

High‐Power Laser Systems

“…For example, gas‐filled hollow‐core PCFs (HC‐PCF) with flexible pressure tunability of the zero‐dispersion wavelength (ZDW) allows the generation of supercontinuum from the deep‐ or vacuum‐ultraviolet region [ 217,219 ] to mid‐infrared. [ 501 ] Recently, supercontinuum generation has extended down to a record 124 nm [ 217 ] and up to 4 µm [ 502 ] based on hydrogen‐filled kagomé‐style HC‐PCF and argon‐filled anti‐resonant HC‐PCF, respectively. Due to the lower transmission loss and better dispersion control than conventional capillaries, gas‐filled HC‐PCFs are also the superior alternative for spectral broadening and pulse compression that can produce 3.8 fs pulses with peak power higher than 0.6 GW.…”