All solid-state diode-pumped Raman laser with self-frequency conversion

Abstract

Operation of an all solid-state compact pulsed Raman laser pumped by a continuous-wave laser diode is demonstrated. The Stokes and anti-Stokes radiations of stimulated Raman scattering at the 1.181 and 0.973 μm wavelengths, respectively, are generated as a result of self-frequency conversion of the 1.067 μm laser radiation in a Nd3+:KGd(WO4)2 crystal. With Q-switched operation, the Raman laser threshold corresponds to 230 mW of a laser diode light power. The output power of 4.8 mW is achieved at the Stokes wavelength with a kilohertz repetition rate.

Analysis of energy characteristics of a ring-cavity Raman laser

“…The cavity of a SRS-generator at the Stokes frequency should have high gain because of the weakness of the SRS-gain effect. The R value differed from unity in the third and fourth terms in published studies of cw SRS-generation [3][4][5][6][7]. Considering this, the dependence of N on z could be neglected in Eq.…”

“…If the dependence on z of the overlap integral M(z) is neglected in Eqs (3). and(4), for example, is replaced by the average value ∫ 0 l M(z)dz ⁄ l = μ/l, then an analytical solution is possible without using the assumption in Eq.…”

“…Stimulated Raman scattering (SRS) is currently widely used for transforming the frequency of laser radiation. Such transformation is very often achieved by placing a scattering medium in a pump laser cavity [1][2][3][4][5] or in a medium in a specially created cavity with external pumping [6,7], i.e., by actually fabricating a SRS-laser. Use of a cavity can significantly decrease the threshold and increase the efficiency of SRS-transformation (SRS-generation) and transform frequencies of weak cw lasers, which is of great practical interest for many laser applications.…”

Compact Diode-Side-Pumped Stimulated Raman Laser Based on a KGW:Nd Crystal

“…Each array emits pulses at λ = 808-810 nm with peak power up to 1 kW. Stimulated Raman conversion is accomplished by self-conversion [2,5], in which the KGW:Nd laser crystal acts as the Raman-active medium.In order to achieve the stimulated Raman conversion threshold, the active laser elements are placed near output mirror 6 ( Fig. 1), having the maximum refl ection coeffi cient at the fundamental wavelength (1.351 μm) and a refl ection coeffi cient equal to 60% (variant No.…”

“…Each array emits pulses at λ = 808-810 nm with peak power up to 1 kW. Stimulated Raman conversion is accomplished by self-conversion [2,5], in which the KGW:Nd laser crystal acts as the Raman-active medium.…”