Timothy Oshiobughie Imogore

• Friedrich Schiller University Jena

We present the realization of phase-shifted FBGs via post-processing using ultrashort laser pulses. Herein, we study the influence of the initial FBG parameters in combination with different extensions of the post-processed region onto the spectrum.

We present the realization of tailored apodization profiles of femtosecond written FBGs using phase mask scanning technique with aperture shaping. By controlling the cross-sectional dimension of the refractive index modification, the spectral response is formed.

We present the inscription of narrow-linewidth fiber Bragg gratings (FBGs) into different types of multicore fibers (MCFs) using ultrashort laser pulses and the phase mask technique, which can act as notch filters. Such filters are required, e.g., to suppress light emitted by hydroxyl in the Earth’s upper atmosphere, which disturbs ground-based obs...

We present an in-depth study on the evolution of the average refractive index profile of an inscribed fiber Bragg grating with respect to the femtosecond laser post-processing parameters. Herein, its influence on the spectral properties of the FBG is discussed.

We present the inscription of fiber Bragg gratings (FBG) into multicore fiber (MCF) as wavelength filter for the suppression of atmospheric emission lines. By applying the phase mask technique and ultrashort laser pulses we can homogeneously modify all cores of a seven core MCF. To overcome intrinsic core-to-core variations, we present a method of...

We present the tuning of the dispersion properties of a femtosecond (fs) laser inscribed chirped fiber Bragg grating (CFBG), realized by selectively modifying the refractive index of the already inscribed CFBG by fs laser post-processing. This Letter demonstrates for the first time, to the best of our knowledge, a flexible approach for tailoring hi...

We present an innovative concept of a semi-aperiodic phase mask design that enables the realization of multi-notch fiber Bragg gratings (FBG). This design utilizes the overlap and interference of near-infrared ultrashort laser pulses diffracted by short sequenced phase mask sections, which not only allows for a highly stable and reproducible inscri...