Upconversion-pumped femtosecond thulium laser at 2309 nm mode-locked by a GaSb-based SESAM.

We report on a femtosecond thulium laser operating on the H → H transition with upconversion pumping around 1 µm and passively mode-locked by a GaSb-based SEmiconductor Saturable Absorber Mirror (SESAM). This laser employs a 6 at.% Tm:LiYF laser crystal and a polarization maintaining Yb-fiber master oscillator power amplifier at 1043 nm as a pump source addressing the F → F excited-state absorption transition of Tm ions.

The 6:1 short stitch SL-WL-ratio: short term closure results of transverse and midline incisions in elective and emergency operations.

Aim: To analyze laparotomy closure quality (suture/wound length ratio; SL/WL) and short term complications (surgical site occurrence; SSO) of conventional midline and transverse abdominal incisions in elective and emergency laparotomies with a longterm, absorbent, elastic suture material.

Method: Prospective, monocentric, non-randomized, controlled cohort study on short stitches with a longterm resorbable, elastic suture (poly-4-hydroxybutyrate, [p-4OHB]) aiming at a 6:1 SL/WL-ratio in midline and transverse, primary and secondary laparotomies for elective and emergency surgeries.

Results: We included 351 patients (♂: 208; ♀: 143) with midline (n = 194), transverse (n = 103), and a combined midline/transverse L-shaped (n = 54) incisions.

Gigahertz semiconductor laser at a center wavelength of 2 µm in single and dual-comb operation.

Dual-comb lasers are a new class of ultrafast lasers that enable fast, accurate and sensitive measurements without any mechanical delay lines. Here, we demonstrate a 2-µm laser called MIXSEL (Modelocked Integrated eXternal-cavity Surface Emitting Laser), based on an optically pumped passively modelocked semiconductor thin disk laser. Using III-V semiconductor molecular beam epitaxy, we achieve a center wavelength in the shortwave infrared (SWIR) range by integrating InGaSb quantum well gain and saturable absorber layers onto a highly reflective mirror.

Single-cavity dual-modelocked 2.36-µm laser.

We present the first dual-modelocked femtosecond oscillator operating beyond 2 µm wavelength. This new class of laser is based on a Cr:ZnS gain medium, an InGaSb SESAM for modelocking, and a two-surface reflective device for spatial duplexing of the two modelocked pulse trains (combs). The laser operates at 2.

50-W average power Ho:YAG SESAM-modelocked thin-disk oscillator at 2.1 µm.

Ultrafast laser systems operating with high-average power in the wavelength range from 1.9 µm to 3 µm are of interest for a wide range of applications for example in spectroscopy, material processing and as drivers for secondary sources in the XUV spectral region. In this area, laser systems based on holmium-doped gain materials directly emitting at 2.