Czochralski-grown LaxGdyRzSc4-x-y-z(BO3)4 (R = Yb, Nd) crystals - A review of recent developments

Abstract Bifunctional crystals, in which the laser effect and a nonlinear optical (NLO) process, e.g. frequency doubling, can occur simultaneously, play a key role in the development of new laser sources with emission in the near-infrared (NIR) or visible (VIS) spectral ranges, with properties adapted to specific applications. As a result, many researches are now devoted to the development of new bifunctional crystals and/or the improvement of the specific properties of existing ones. In this review, we focus on our recent work on Czochralski-grown undoped, Yb- and Nd-doped LaxGdySc4-x-y(BO3)4 - LGSB crystals as efficient bifunctional laser and NLO crystals. Structural, linear and NLO properties, as well as NIR laser emission performances in the case of Yb- and Nd-doped crystals are reported. The results prove that all these crystals have good NLO properties, characteristic to huntite-type crystals. A remarkable advantage of the Czochralski-grown LGSB crystal is that it can be grown with large size and high quality, which makes it a very promising candidate for various NLO applications, especially for frequency conversion through SHG processes of the high-average power NIR laser radiation into VIS radiation. In addition, the good NLO properties of the Yb:LGSB and Nd:LGSB crystals, together with the advantage to grow large size and high-quality crystals by the Czochralski technique, and the excellent NIR laser performances demonstrated experimentally, recommend Yb:LGSB and Nd:LGSB as promising bifunctional crystals to design new laser sources in the NIR and green spectral ranges based on direct laser emission and self-frequency doubling processes, respectively.