Half mJ Supercontinuum Generation in a Telecommunication Multimode Fiber by a Q-switched Tm, Ho:YVO₄Laser

Abstract

Up to ~520 µJ broadband mid-infrared (IR) supercontinuum (SC) generation in telecommunication multimode fiber (MMF) directly pumped by a 2.054 μm nanosecond Q-switched Tm,Ho:YVO4 laser is demonstrated. An average output power of 3.64 W is obtained in the band of ~1900 to ~2600 nm, and the corresponding optic-to-optic conversion efficiency is 67% by considering the coupling efficiency. The spectrum has extremely high flatness with negligible intensity variation (<2%) in the wavelength interval of ~2070 to ~2475 nm. The SC long-wavelength edge is limited by the silicon glass material loss, and by optimizing the MMF length, the SC spectrum could extend out to ∼2.6 µm. The output SC pulse shapes are measured at different output powers, and no splits are found. The SC laser beam is nearly diffraction limited with an M 2 =1.15 in 2.1 μm measured by the traveling knife-edge method, and the laser beam spot is monitored by an infrared vidicon camera.

Spectral-temporal-spatial customization via modulating multimodal nonlinear pulse propagation

“…The intricate nonlinear interactions emphasize the benefits of using a fiber shaper to control the spatiotemporal dimension of the nonlinear dynamics in order to achieve a targeted output in different dispersion regimes. Earlier studies have successfully demonstrated broadband supercontinuum generation using silica MMFs in longer pulse duration regimes 8 – 11 , 21 , 71 . In this work, we demonstrate a two-octave tunable source in the femtosecond regime, which enables applications in multiphoton microscopy due to its high-peak-power pulses.…”

Infrared Saturable Absorption Properties of Tungstenene Nanosheets for Passively Q-Switched 1.9 μm Solid-State Laser

“…Pulsed lasers of nearly 2 μm have played an important role in industrial, military, and scientific research fields. − As an effective means to obtain a pulsed laser, passively Q-switched (PQS) technology has the advantages of simple structure, easy operation, and low cost. A high-quality saturable absorber (SA) is the key component for PQS.…”