Theoretical study on absorption efficiency for a LD side-pumped Nd:YAG laser with the infinite convergence approach

• Published in: Infrared physics & technology Vol. 44; no. 3; pp. 213 - 225
• Main Authors: Wang, You, Hirano, Isuke, Kan, Hirofumi
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.06.2003; Elsevier
• Subjects: Absorption efficiency; Diffusing chamber; Doped-insulator lasers and other solid state lasers; Efficiency, stability, gain, and other operational parameters; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Laser optical systems: design and operation; Lasers; LD side-pumped Nd:YAG Lasers; Optics; Physics; Random reflection; Ray trace; Resonators, cavities, amplifiers, arrays, and rings; 42.55.Rz; 42.60.Da; 42.60.Lh; LD side-pumped Nd:YAG Lasers; Random reflection; Diffusing chamber; Ray trace; Absorption efficiency; Solid state lasers; Laser pumping; YAG laser; Theoretical study; Ray tracing; Total absorption; Laser diodes; Neodymium lasers
• ISSN: 1350-4495; 1879-0275
• DOI: 10.1016/S1350-4495(02)00211-6

We present a new technique to analyze the absorption efficiency of the active medium for a LD side-pumped Nd:YAG laser. A detailed ray trace has been carried out to evaluate the route of the pump LD-rays propagating inside the diffusing chamber. The method, named the infinite convergence approach, is used to determine the total absorbed power of a Nd:YAG rod when random reflection takes place at the inner surface of the reflector wall. By reason of losses caused by slits milled the reflector wall, there is an optimum slit width corresponding to the maximum absorption efficiency. It has been theoretically determined that the absorption efficiency can be summarized by a convergent result for the infinite energy transfer process inside the diffusing chamber. The method is applicable to the cavity design for any LD side-pumped solid-state lasers.