Title :
Stable single-frequency fiber ring laser for 25-GHz ITU-T grids utilizing saturable absorber filter
Author :
Ryu, Han Young ; Lee, Won-Kyu ; Moon, Han Seb ; Kim, Seung Kwan ; Suh, Ho Suhng ; Lee, Donghan
Author_Institution :
Div. of Opt. Metrol., Korea Res. Inst. of Stand. & Sci., Daejeon, South Korea
Abstract :
A stable single-frequency fiber ring laser is proposed that operates in a single mode for more than an hour by incorporating unpumped erbium-doped fiber (EDF) as a saturable absorber filter and optimizing the length of EDF used as gain medium. This laser can be continuously tuned to 25-GHz spacing that precisely matches the ITU-T grids by temperature control of etalon filter. This laser had a signal-to-source spontaneous emission ratio higher than 70 dB, and lasing frequencies of 361 channels was matched to ITU-T grids with excellent flatness. Frequency offset from the ITU-T grid was less than 0.14 GHz. The linewidth and the relative intensity noise value was less than 1.3 kHz and 130 dB/Hz (above 250 kHz), respectively.
Keywords :
Fabry-Perot interferometers; channel spacing; erbium; fibre lasers; laser frequency stability; laser noise; laser tuning; optical communication equipment; optical fibre filters; optical saturable absorption; ring lasers; spontaneous emission; temperature control; ITU-T grids; etalon filter; laser tuning; linewidth; relative intensity noise; saturable absorber filter; single-frequency fiber ring laser; spontaneous emission ratio; temperature control; unpumped erbium-doped fiber; Erbium-doped fiber lasers; Fiber lasers; Frequency; Laser modes; Laser noise; Laser stability; Laser tuning; Matched filters; Ring lasers; Temperature control; Fabry–PÉrot filter; ITU-T grids; saturable absorber; single mode;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2005.851926
