Diode-bar side-pumping of double-clad fibers

Sean W. Moore; Jeffrey P. Koplow; Andrea Hansen; Georg Wien; Dahv A. V. Kliner

doi:10.1117/12.702015

20 February 2007 Diode-bar side pumping of double-clad fibers

Sean W. Moore, Jeffrey P. Koplow, Andrea Hansen, Georg Wien, Dahv A. V. Kliner

Proceedings Volume 6453, Fiber Lasers IV: Technology, Systems, and Applications; 64530K (2007) https://doi.org/10.1117/12.702015
Event: Lasers and Applications in Science and Engineering, 2007, San Jose, California, United States

Abstract

We demonstrate direct diode-bar side pumping of a Yb-doped fiber laser using embedded-mirror side pumping (EMSP). In this method, the pump beam is launched by reflection from a micro-mirror embedded in a channel polished into the inner cladding of a double-clad fiber (DCF). The amplifier employed an unformatted, non-lensed, ten-emitter diode bar (20 W) and glass-clad, polarization-maintaining, large-mode-area fiber. Measurements with passive fiber showed that the coupling efficiency of the raw diode-bar output into the DCF (ten launch sites) was ~84%; for comparison, the net coupling efficiency using a conventional, formatted, fiber-coupled diode bar is typically 50-70%, i.e., EMSP results in a factor of 2-3 less wasted pump power. The slope efficiency of the side-pumped fiber laser was ~80% with respect to launched pump power and 24% with respect to electrical power consumption of the diode bar; at a fiber-laser output power of 7.5 W, the EMSP diode bar consumed 41 W of electrical power (18% electrical-to-optical efficiency). When end pumped using a formatted diode bar, the fiber laser consumed 96 W at 7.5 W output power, a factor of 2.3 less efficient, and the electrical-to-optical slope efficiency was lower by a factor of 2.0. Passive-fiber measurements showed that the EMSP alignment sensitivity is nearly identical for a single emitter as for the ten-emitter bar. EMSP is the only method capable of directly launching the unformatted output of a diode bar directly into DCF (including glass-clad DCF), enabling fabrication of low-cost, simple, and compact, diode-bar-pumped fiber lasers and amplifiers.

Citation Download Citation

Sean W. Moore, Jeffrey P. Koplow, Andrea Hansen, Georg Wien, and Dahv A. V. Kliner "Diode-bar side pumping of double-clad fibers", Proc. SPIE 6453, Fiber Lasers IV: Technology, Systems, and Applications, 64530K (20 February 2007); https://doi.org/10.1117/12.702015

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available