Low‐wavelength emission of Nd‐doped lasers

Abstract

This paper gives an overview of the results obtained with diode-pumped Neodymium-doped crystals operating below 900 nm. Operation at such low wavelengths requires considering the strong thermal population of the lower level of the laser transition. Based on a theoretical study and simulations, the paper presents the challenges related to the design of these three-level lasers. Experimental results are given with Nd:YAG and Nd:vanadate crystals. It is explained how to deal with the line competition with emission at 946 nm or 912 nm. Finally, intracavity second-harmonic generation is presented. The output powers reach a few hundred mW at wavelengths below 450 nm. Hence, the paper demonstrates the potential of Nd-doped diodepumped solid-state lasers for applications in the blue range, in replacement of gas lasers such as helium-cadmium lasers.

250 W single-crystal fiber Yb:YAG laser

“…This reveals the high potential of single-crystal fiber technology providing both high gain and significant extraction efficiency for power amplifier design. In order to study the impact of the intensity profile on extraction efficiency, we modelized our singlecrystal fiber amplifier using a similar method to what is described in [8]. Two cases were considered for the signal: a 700 μm diameter flat-top beam and a 500 μm Gaussian beam.…”

Diode-pumped Nd:YVO4-Nd:CNGG crystals blue laser at 462 nm by intracavity sum-frequency-mixing

“…Coherent cw light sources in the visible region are important for a number of scientific and technical applications including metrology, remote sensing, biotechnology, communications, and display technology [1][2][3][4][5][6]. In past few years, new solid sate lasers were designed to enlarge the panel of wavelengths, for examples, in the yellow range [7,8], or to improve sources that have already been used, as in the blue range [9,10].…”

Fine wavelength control in 1.3 μm Nd:YAG lasers by electro-optical crystal lens

“…In order to obtain the single-wavelength output in narrow band range, an etalon is usually inserted in the cavity to select wavelength. [4][5][6] However, when tuning with the etalon, mechanical rotation is necessary, which lowers the adjusting accuracy and can only realize single-wavelength output. In this paper, we propose a new tunable method for narrow band range by applying an adjustable voltage to the KH 2 PO 4 (KDP) crystal lens.…”