Related papers: Demonstration of fundamental mode only propagation…
We report the flexible on-target delivery of 800 nm wavelength, 5 GW peak power, 40 fs duration laser pulses through an evacuated and tightly coiled 10 m long hollow-core nested anti-resonant fiber by positively chirping the input pulses to…
In this contribution we investigate the transversal mode instability behavior of an ytterbium doped commercial 20/400 fiber and obtain 2.9 kW of output power after optimizing the influencing parameters. In this context, we evaluate the…
We present the design and characterization of waveguide grating devices that couple visible-wavelength light at $\lambda=674$ nm from single-mode, high index-contrast dielectric waveguides to free-space beams forming micron-scale…
High-power fiber laser amplifiers have enabled an increasing range of applications in industry, medicine and defense. The power scaling for narrow-band amplifiers is currently limited by the transverse modal instability. Various techniques…
In this work we analyze the power scaling potential of amplifying multicore fibers (MCFs) used in coherently-combined systems. In particular, in this study we exemplarily consider rod-type MCFs with 2x2 up to 10x10 Ytterbium doped cores…
We present empirical formulae that can provide dispersion and average effective area of the fundamental mode in hollow-core antiresonant fibers. The formulae draw on the structural parameters of the fiber, and allow one to obtain the…
We experimentally demonstrate a passively Q-switched erbium-doped fiber laser (EDFL) operation by using a saturable absorber based on Fe3O4 nanoparticles (FONP) in magnetic fluid (MF). As a kind of transition metal oxide, the FONP has a…
There are several high-performance adaptive optics systems that deliver diffraction-limited imaging on ground-based telescopes, which renewed the interest of single-mode fiber (SMF) spectroscopy for exoplanet characterization. However, the…
A micro-optics device has been developed to limit backreflection at the end face of single-mode fibers. The measured return loss at a wavelength of 1.55 m is as high as 28 dB. This device allows for preservation of the geometric aspect of a…
We evaluate large-core FSO links where excellent coupling pairs with bandwidth fading due to multi-mode propagation. The 10-Gb/s/{\lambda} limit for 105-{\mu}m double-clad fibers is mitigated by spectral launch tuning, restoring 84% of…
Femtosecond laser micromachining (FLM) fabricated waveguides inherently form elliptical cores due to differences in focal spot size and the Rayleigh range of the microscope objective. Consequently, it is essential to study their propagation…
Enormous fluid antenna systems (E-FAS), the system concept that utilizes position reconfigurability in the large scale, have emerged as a new architectural paradigm where intelligent surfaces are repurposed from passive smart reflectors…
The resolution of far-field optical microscopes, which rely on propagating optical modes, is widely believed to be limited because of diffraction to a value on the order of a half-wavelength $\lambda /2$ of the light used. Although…
Dielectric waveguide (DWG) interconnects frequently utilize multimode waveguides due to their low dispersion in the fundamental mode. However, these links are more vulnerable to cross-modal coupling that significantly impacts their overall…
We report on a mid-infrared mode-locked fiber laser that uses an acousto-optic tunable filter to achieve frequency-shifted feedback pulse generation with frequency tuning over a 215 nm range. The laser operates on the 3.5 ${\mu}$m…
We present a simple technique to produce active Q-switching in various types of fiber amplifiers by active integration of an electrostatic actuated deformable metallic micro-mirror. The optical MEMS (MOEMS) device acts as one of the laser…
We present a 2-\mum frequency comb based on a reliable mode-locked Er:fiber laser with 100 MHz repetition rate. After shifting the spectrum of the amplified Er:fiber comb to longer wavelengths, a single-clad Tm/Ho:fiber is used as a…
A large mode area single-mode optical fibre based on leaky mode filtering was prepared by MCVD. The cladding structure discriminates the fundamental mode from the higher order ones. A preliminary version has 25-$\mu$m core diameter and 0.11…
We report on an anti-resonant hollow-core fiber (AR-HCF) designed for stable transmission of laser light in a broad wavelength range of 250 nm to 450 nm. We tested for wavelengths of 300 nm and 320 nm. The characterized fiber shows a low…
Dependence of mode instabilities (MI) on ytterbium dopant concentrations in high power fiber amplifiers has been investigated. It is theoretically shown that, by only varying the fiber length to maintain the same total small-signal pump…