Title :
Continuous-wave frequency synthesis of a laser diode based on discrete-time negative frequency feedback. I. Experiment
Author :
Shimizu, Kaoru ; Sakai, Yoshihisa ; Horiguch, Tsuneo ; Koyamada, Yahei
Author_Institution :
NTT Access Network Syst. Labs., Ibaraki, Japan
fDate :
6/1/1995 12:00:00 AM
Abstract :
The absolute frequency synthesis of a distributed-feedback (DFB) laser diode (LD) is demonstrated by use of a loss-compensated optical ring circuit with a frequency shifter and a frequency-stabilized master laser system containing an acetylene (13C2H2 ) absorption cell. A lightwave from the master laser is modulated into a pulse and circulated around the ring to shift its frequency in the 0~100 GHz range. A continuous-wave from the DFB LD is mixed with a recirculated pulse with a desirable reference frequency, and their beat frequency is counted in order to obtain the error signal. The absolute frequency of the DFB LD is locked to the reference frequency based on discrete-time negative frequency feedback control for the injection current. The accuracy of the absolute frequency was experimentally confirmed to be within a few MHz for an averaging time of 1 s and an operation time of 1 hour
Keywords :
compensation; distributed feedback lasers; laser frequency stability; light absorption; optical modulation; semiconductor lasers; 0 to 100 GHz; 13C2H2 absorption cell; DFB LD; DFB laser diode; absolute frequency synthesis; acetylene; averaging time; beat frequency; continuous-wave frequency synthesis; discrete-time negative frequency feedback; distributed-feedback laser diode; error signal; frequency shifter; frequency-stabilized master laser system; laser diode; loss-compensated optical ring circuit; master la; operation time; recirculated pulse; reference frequency; Absorption; Circuit synthesis; Diode lasers; Frequency synthesizers; Optical feedback; Optical losses; Optical modulation; Optical pulses; Pulse modulation; Ring lasers;
Journal_Title :
Quantum Electronics, IEEE Journal of
