Open AccessOptical pump phase locking to a carrier wave extracted from phase-conjugated twin waves for phase-sensitive optical amplifier repeaters
Author(s) -
Yasuyuki Okamura,
Matazō Abe,
Kotaro Kondo,
Yuya Ohmichi,
Takushi Kazama,
Takeshi Umeki,
Masafumi Koga,
Atsushi Takada
Publication year - 2016
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.026300
Subject(s) - optics , optical parametric amplifier , materials science , amplifier , phase (matter) , optical amplifier , phase locked loop , second harmonic generation , physics , optoelectronics , phase noise , laser , cmos , quantum mechanics
In this paper, an optical phase-locked loop assisted by sum-frequency and second-harmonic generation (SS-OPLL) for frequency nondegenerate optical parametric phase-sensitive amplifier repeaters is experimentally demonstrated. First, theoretical derivations show that carrier extraction from phase-conjugated twin waves (PCTWs) and reference light generation are achieved by sum-frequency generation; therefore, the SS-OPLL circuit enables optical phase locking between PCTWs and a pump wave by a simple architecture based on a balanced OPLL. Then, optical phase locking between 20-Gbit/s quadrature phase-shift keying PCTWs and an individual pump source is experimentally demonstrated. Experimental results indicate that phase errors were reduced during the SS-OPLL operation.