Carbon nanotube Q-switched Yb:KLuW surface channel waveguide lasers

Abstract

A channel waveguide (WG) buried immediately below the surface of a Yb:KLuW crystal is used as a laser gain medium for passive Q-switching by both evanescent-and directfield interactions with single-walled carbon nanotubes (SWCNTs) near 1040 nm. The SWCNTs used as saturable absorbers (SAs) are deposited on top of the half-ring-type channel WG fabricated via femtosecond direct laser writing. The Q-switched WG laser delivers 88.5 ns pulses at a 1.16 MHz repetition rate with a maximum average output power of 680 mW. For the two different interaction schemes with SWCNT-SAs, the pulse characteristics, depending on the output coupling ratio and absorbed pump power, are experimentally investigated and compared to the results of theoretical analyses of the SA Q-switched operation.

Controllable Dynamic Single‐ and Dual‐Channel Graphene Q‐Switching in a Beam‐Splitter‐Type Channel Waveguide Laser

“…[2,[13][14][15][16] One of the most critical conditions for a suitable saturable absorber (SA) for passive Q-switching or mode-locking of compact lasers is its flexible integrability in a laser cavity. Low-dimensional nanocarbons such as graphene and carbon nanotubes have been successfully recognized as suitable SAs in Q-switched [17][18][19][20][21] and mode-locked Yb 3+ -doped fs-DLW WG lasers. [22][23][24][25] They exhibit superior optical properties including ultra-broadband nonlinear absorption, large nonlinearity and ultrafast relaxation time, and enable a relatively low cost and facile fabrication process.…”

Crystalline waveguides with carbon nanomaterials for miniaturized pulsed lasers - INVITED

“…To effectively combine nanomaterials into waveguides, interaction types of SWCNTs are comparatively studied in waveguides placed near the surface [6,7]. Evanescentfield interaction provides monolithic integration of materials with more efficient Q-switched operation than direct type, and prevents thermal damage issues (Fig.…”

Near‐Infrared All‐Optical Switching Based on Nano/Micro Optical Structures in YVO4 Matrix: Embedded Plasmonic Nanoparticles and Laser‐Written Waveguides

“…At the same time, waveguide‐based pulsed lasing has attracted more and more attention in recent years. [ 27–33 ] Femtosecond laser writing has emerged as a powerful tool to fabricate 3D microstructures inside the transparent functional materials. [ 34–38 ] With the light confinement within the microstructures, the intracavity light intensity can be greatly enhanced with lower lasing thresholds and enhanced slope efficiencies compared with bulk systems.…”