Fiber-laser frequency combs with subhertz relative linewidths.
We investigate the comb linewidths of self-referenced, fiber-laser-based frequency combs by measuring the heterodyne beat signal between two independent frequency combs that are phase locked to a common cw optical reference. We demonstrate that the optical comb lines can exhibit instrument-limited, subhertz relative linewidths across the comb spectra from 1200 to 1720 nm with a residual integrated optical phase jitter of approximately 1 rad in a 60 mHz to 500 kHz bandwidth. The projected relative pulse timing jitter is approximately 1 fs. This performance approaches that of Ti:sapphire frequency combs.
Swann
W C
WC
National Institute of Standards and Technology, Boulder, Colorado 80305, USA.
McFerran
J J
JJ
Coddington
I
I
Newbury
N R
NR
Hartl
I
I
Fermann
M E
ME
Westbrook
P S
PS
Nicholson
J W
JW
Feder
K S
KS
Langrock
C
C
Fejer
M M
MM