Excitation of high-radial-order Laguerre–Gaussian modes in a solid-state laser using a lower-loss digitally controlled amplitude mask. (13th September 2017)

• Record Type: Journal Article
• Authors: Bell, T; Hasnaoui, A; Ait-Ameur, K; Ngcobo, S
• Is Part Of: Journal of optics. Volume 19:Number 10(2017:Oct.)
• Publication Date: 2017-09-13
• Subjects: solid-state lasers -- laser resonators -- spatial light modulators -- laser beam characterization; 42.40.Jv -- 42.55.-f -- 42.55.Xi -- 42.60.Da; Optics -- Periodicals; 535.05
• DOI: 10.1088/2040-8986/aa81f9
• Languages: English
• ISSNs: 2040-8978

Abstract

Abstract: In this paper we experimentally demonstrate selective excitation of high-radial-order Laguerre–Gaussian (LG p or LG p, 0 ) modes with radial order p = 1–4 and azimuthal order l = 0 using a diode-pump solid-state laser (DPSSL) that is digitally controlled by a spatial light modulator (SLM). We encoded an amplitude mask containing p -absorbing rings, of various incompleteness (segmented) on grey-scale computer-generated digital holograms, and displayed them on an SLM which acted as an end mirror of the diode-pumped solid-state digital laser. The various incomplete ( α ) p -absorbing rings were digitally encoded to match the zero-intensity nulls of the desired LG p mode. We show that the creation of LG p, for p = 1 to p = 4, only requires an incomplete circular p -absorbing ring that has a completeness of ≈37.5%, giving the DPSSL resonator a lower pump threshold power while maintaining the same laser characteristics (such as beam propagation properties).