Efficient 1 µm Laser Emission of Czochralski-Grown Nd:LGSB Single Crystal

Materials

Traian Dascalu¹  Lucian Gheorghe¹  Stefania Hau¹  Catalina-Alice Brandus¹  Cristina Gheorghe¹  Flavius-Marian Voicu¹  Madalin Greculeasa¹  Alin Broasca¹ 

[1] National Institute for Laser, Plasma and Radiation Physics, Laboratory of Solid-State Quantum Electronics, Atomistilor 409, Magurele 077125, Ilfov, Romania;

关键词: Nd-doped borate crystals;    end pumping;    passive Q-switching;    SESAM mode-locking;   

DOI  :  10.3390/ma12122005

来源: DOAJ

【 摘 要 】

A 5.0-at.% Nd-doped La_0.64Gd_0.41Sc_2.95(BO₃)₄ (Nd:LGSB) borate laser crystal was successfully grown by the Czochralski method, for the first time to our knowledge. The spectroscopic properties of the grown crystal are discussed and 1 µm laser emission, under end-pumping with a fiber-coupled diode laser at 807 nm, is reported. A c-cut Nd:LGSB medium yielded 1.35 W continuous-wave output power at 0.63 overall optical-to-optical efficiency, with respect to the absorbed pump power, together with the high 0.68 slope efficiency. With an a-cut Nd:LGSB sample, 0.81 W output power at 0.52 optical-to-optical efficiency was obtained. The laser emission performances under quasi-continuous wave pumping are presented as well, for both c-cut and a-cut crystals. Passive Q-switching was investigated with a semiconductor saturable absorber mirror (SESAM). Laser pulses with 2.2 µJ energy and 32.8 ns durations were recorded from a-cut Nd:LGSB. The average output power reached 0.36 W at 1.55 W absorbed pump power. Passive mode-locking with SESAM was achieved in a long Z-type resonator. Ultrashort pulses with 0.19 W average power, 1.63 nJ energy, and 1.43 ps pulse duration, at 118 MHz repetition rate, are demonstrated for the a-cut Nd:LGSB medium.

【 授权许可】

Unknown