Continuous-wave broadly tunable high-power Cr:CdS laser

• Published in: Applied physics. B, Lasers and optics Vol. 117; no. 4; pp. 1009 - 1014
• Main Authors: Sorokin, E., Klimentov, D., Frolov, M. P., Korostelin, Yu. V., Kozlovsky, V. I., Podmar’kov, Yu. P., Skasyrsky, Ya. K., Sorokina, I. T.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 2014
• Subjects: Calcium fluoride; Cross sections (physics); Engineering; Laser pumping; Lasers; Luminescence; Optical Devices; Optics; Photonics; Physical Chemistry; Physics; Physics and Astronomy; Prisms; Quantum Optics; Slopes; Spectroscopy; Emission Cross Section; ZnSe; Slope Efficiency; Tuning Range; Absorb Pump Power
• ISSN: 0946-2171; 1432-0649
• DOI: 10.1007/s00340-014-5921-z

We report spectroscopic characteristics and laser properties of the mid-infrared active laser medium Cr
2+
:CdS. Temperature-dependent absorption, luminescence and lifetime measurements of the
5
E exited state allow determination of peak emission cross section value of 1.35 × 10
−18
 cm
2
in
σ
-polarization at room temperature. Lifetime values vary from 7.6 µs at 8 K to 0.48 µs at 320 K, corresponding to 22 % quantum yield at 285 K. Under Tm-fiber laser pumping, the continuous-wave output reached 1.8 W at 2.5 μm with 35.5 % slope efficiency. With a single CaF
2
prism, the CW Cr
2+
:CdS laser could be tuned from 2.240 to 3.285 µm.