Long-term optical phase locking between femtosecond Ti:sapphire and Cr:forsterite lasers.
Long-term optical phase-coherent two-color femtosecond pulses were generated by use of passively timing-synchronized Ti:sapphire and Cr:forsterite lasers. The relative carrier-envelope phase relation was fixed by an active feedback loop. The accumulated phase noise from 10 mHz to 1 MHz of the locked beat note was 0.43 rad, showing tight phase locking. The optical frequency fluctuation between two femtosecond combs was submillihertz, with a 1 s averaged counter measurement over 3400 s, leading to a long-term femtosecond frequency-comb connection.
Kobayashi
Yohei
Y
National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba 305-8568, Japan. y.kobayashi@aist.go.jp
Yoshitomi
Dai
D
Kakehata
Masayuki
M
Takada
Hideyuki
H
Torizuka
Kenji
K