Open AccessMode density multiplication of an optical frequency comb by N2 with phase modulation
Author(s) -
Tsunemi Hasegawa
Publication year - 2018
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.26.024551
Subject(s) - optics , phase modulation , modulation (music) , phase (matter) , multiplication (music) , frequency comb , mode locking , materials science , physics , laser , phase noise , quantum mechanics , acoustics
We introduce a simple scheme for mode-density multiplication of an optical frequency comb (OFC) by a factor of square of an arbitrary integer N using phase modulation. This scheme is employed to multiply the mode density of an erbium-doped fiber laser OFC (repetition rate of 66.87 MHz) by factors of 4 2 , 8 2 , and 3 · 4 2 using an electro-optic phase modulator. The OFC multiplied by 4 2 is applied to direct-comb spectroscopy of methane with a spectral resolution of 4.18 MHz.