Single-mode operation of a coiled multimode fiber amplifier

Journal Article · Wed Jan 19 04:00:00 EST 2000 · Optics Letters

OSTI ID:751138

Koplow, Jeffrey P; Kliner, Dahv A. V.; Goldberg, Lew

The authors report a new approach to obtain single-transverse-mode operation of a multimode fiber amplifier, in which the gain fiber is coiled to induce significant bend loss for all but the lowest-order mode. They have demonstrated this method by constructing a coiled amplifier using Yb-doped, double-clad fiber with a core diameter of 25 {micro}m and NA of {minus}0.1 (V {approx} 7.4). When operated as an ASE source, the output beam had an M{sup 2} value of 1.09 {+-} 0.09; when seeded at 1,064 nm, the slope efficiency was similar to that of an uncoiled amplifier. This technique does not require exotic fiber designs or increase system complexity and is inexpensive to implement. It will allow scaling of pulsed fiber lasers and amplifiers to significantly higher pulse energies and peak powers and cw fiber sources to higher average powers while maintaining excellent beam quality.

• Research Organization: Sandia National Labs., Albuquerque, NM (US); Sandia National Labs., Livermore, CA (US)
• Sponsoring Organization: US Department of Energy (US)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 751138
• Report Number(s): SAND2000-8522J; ISSN 0146-9592
• Journal Information: Optics Letters, Journal Name: Optics Letters
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
AMPLIFIERS
FIBERS
MODE SELECTION
OPERATION
SCALING LAWS
SOLID STATE LASERS