Phase shaping of dual-pumped Brillouin-Kerr frequency combs.

We investigate the spectral phase characteristics of dual-pumped Kerr frequency combs generated in a bichromatic Brillouin fiber laser architecture with normal dispersion, producing square-like pulse profiles. Using a pulse shaper, we measure the relative phase between the pump Stokes and adjacent lines, revealing a symmetric phase relationship. Our results highlight good phase coherence of the comb.

Dispersion engineering in a Brillouin fiber laser cavity for Kerr frequency comb formation.

We conduct numerical and experimental investigations on Kerr comb generation in a nonlinear and non-reciprocal fiber cavity by leveraging both stimulated Brillouin backscattering and cascaded four-wave mixing. By engineering the net cavity dispersion to be either normal or anomalous, we enable the formation of diverse patterns and localized structures in the cavity field. The comb's properties depend crucially on the mismatch between the frequency spacing of the bichromatic pump and the free spectral range of the Brillouin laser cavity in both cases.

2-μm Brillouin laser based on infrared nonlinear glass fibers.

Infrared fiber materials such as chalcogenide, tellurite, and heavily germanium-doped silica glasses are attractive materials for many applications based on nonlinear optical effects such as Kerr, Raman, and Brillouin processes. Here, we experimentally demonstrate a close-to-single-frequency Brillouin fiber laser in the 2-μm wavelength region either based on tellurite () glass or on heavily germanium-doped silica glass. Our results reveal a strong enhancement of the Brillouin gain efficiency at 2 μm of more than 50 times that of standard silica optical fibers.

Large Brillouin gain in Germania-doped core optical fibers up to a 98 mol% doping level.

Germanosilicate glasses are substantial materials in fiber optic technology that have allowed the control of optical properties such as numerical aperture, photosensitivity, dispersion, nonlinearity, and transparency toward mid-infrared. Here, we investigate stimulated Brillouin scattering in single-mode germanosilicate core fibers with increasing GeO content from 3.6 mol% up to 98 mol%.