27 W 2.1 µm OPCPA system for coherent soft X-ray generation operating at 10 kHz

© 2020 Optical Society of America. Users may use, reuse, and build upon the article, or use the article for text or data mining, so long as such uses are for non-commercial purposes and appropriate attribution is maintained. All other rights are reserved.We developed a high power optical parametric chirped-pulse amplification (OPCPA) system at 2.1 µm harnessing a 500 W Yb:YAG thin disk laser as the only pump and signal generation source. The OPCPA system operates at 10 kHz with a single pulse energy of up to 2.7 mJ and pulse duration of 30 fs. The maximum average output power of 27 W sets a new record for an OPCPA system in the 2 µm wavelength region. The soft X-ray continuum generated through high harmonic generation with this driver laser can extend to around 0.55 keV, thus covering the entire water window (284 eV - 543 eV). With a repetition rate still enabling pump-probe experiments on solid samples, the system can be used for many applications.EC/H2020/654148/EU/The Integrated Initiative of European Laser Research Infrastructures/LASERLAB-EUROP

QUASI-Three-Level Laser Emissions of Neodymium-Doped Disordered Crystal Waveguides

This paper reports on the quasi-three-level continuous wave laser operation based on waveguide structures in neodymium-doped calcium niobium gallium garnet disordered crystal. Laser wavelength selection through the waveguide cross section was observed. Waveguide structures with different cross sections were fabricated by the ultrafast laser inscription, which have propagation losses around 1 dB/cm. With suitable pumping conditions, laser emissions were observed at the low wavelengths of ~930 and ~890 nm. The lasing threshold for the low-wavelength emission was around 50 mW, which is far below the threshold of several watts reported in the bulk laser system. In addition, it was found that the laser generation at the wavelength of ~890 nm has direct relationship with the volume of the waveguide structure. The results suggest advantages of the waveguide platforms over the bulk systems on the low-wavelength laser emission

Tri-wavelength laser generation based on neodymium doped disordered crystal waveguide

[EN]We demonstrate a tri-wavelength laser generation from a Nd-doped calcium niobium gallium garnet disordered crystal waveguide. The laser threshold obtained was 83 mW of launched pumping laser corresponding to a slope efficiency of 5.1%. According to the laser spectrum, the output light was found to be a tri-wavelength laser, with wavelengths of 1058 nm, 1060 nm and 1064 nm, respectively. The stability of the output laser was investigated, which found that the output laser was a continuous laser.This work was carried out under the support by the National Natural Science Foundation of China (No. 11274203), the Spanish Ministerio de Ciencia e Innovación (projects CSD2007-00013 and FIS2009-09522), and the Junta de Castilla y León (project SA086A12-2). Yang Tan acknowledges the support by the Independent Innovation Foundation of Shandong University (IIFSDU, No. 104222012GN056 / 11160072614098) and China Postdoctoral Science Foundation (Grant No. 2013M530316)

27 W 2.1 µm OPCPA system for coherent soft X-ray generation operating at 10 kHz

We developed a high power optical parametric chirped-pulse amplification (OPCPA) system at 2.1 µm harnessing a 500 W Yb:YAG thin disk laser as the only pump and signal generation source. The OPCPA system operates at 10 kHz with a single pulse energy of up to 2.7 mJ and pulse duration of 30 fs. The maximum average output power of 27 W sets a new record for an OPCPA system in the 2 µm wavelength region. The soft X-ray continuum generated through high harmonic generation with this driver laser can extend to around 0.55 keV, thus covering the entire water window (284 eV - 543 eV). With a repetition rate still enabling pump-probe experiments on solid samples, the system can be used for many applications. © 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreemen

Atomic-layer molybdenum sulfide optical modulator for visible coherent light

Coherent light sources in the visible range are playing important roles in our daily life and modern technology, since about 50% of the capability of the our human brains is devoted to processing visual information. Visible lasers can be achieved by nonlinear optical process of infrared lasers and direct lasing of gain materials, and the latter has advantages in the aspects of compactness, efficiency, simplicity, etc. However, due to lack of visible optical modulators, the directly generated visible lasers with only a gain material are constrained in continuous-wave operation. Here, we demonstrated the fabrication of a visible optical modulator and pulsed visible lasers based on atomic-layer molybdenum sulfide (MoS 2), a ultrathin two-dimensional material with about 9-10 layers. By employing the nonlinear absorption of the modulator, the pulsed orange, red and deep red lasers were directly generated. Besides, the present atomic-layer MoS 2 optical modulator has broadband modulating properties and advantages in the simple preparation process. The present results experimentally verify the theoretical prediction for the low-dimensional optoelectronic modulating devices in the visible wavelength region and may open an attractive avenue for removing a stumbling block for the further development of pulsed visible lasers