[OPTICAL REVIEW Vol. 5, No. 2 (1998) 105-108]

Recovery of Laser-Diode Coherence Length by a Photorefractive Double Phase-Conjugate Mirror

Ribun ONODERA,1 Yukihiro ISHII,1 Vasilii V. SPIRIN,2 Alexei A. KAMSHILIN3 and Timo JAASKELAINEN3

1Department of Electronics, University of Industrial Technology, Sagamihara 4-1-1, Hashimotodai, Sagamihara Kanagawa 229-1196, Japan, 2 A.F. Ioffe Physical-Technical Institute, 194021 St. Petersburg, Russia, 3 Väisaälä Laboratory, Department of Physics, University of Joensuu, P.O. Box 111, FIN-80101 Joensuu, Finland

(Received November 10, 1997; Accepted February 16, 1998)

We report an experimental study of dynamic coupling of two laser diodes (LD’s) with a double phase-conjugate mirror (DPCM) in a Bi12TiO20 fiber-like crystal. After the DPCM is recorded in the crystal, one of the LD’s is switched to the multimode regime, while the other remains lasing in the single longitudinal mode. Nevertheless, the DPCM produces phase locking of the single-mode laser with one of the longitudinal modes of the multimode laser. Only the longitudinal mode survives after the transmission through the DPCM, demonstrating the coherence length recovery of the multimode laser.

Key words : photorefractive nonlinear optics - double-phase conjugation - phase locking - laser diodes

Email: onodera@uitec.ac.jp