Sapphire-based graphene saturable absorber for long-time working femtosecond lasers.
We report a long-time working femtosecond laser using metal-free sapphire-based graphene as a saturable absorber (SA). The sapphire-based graphene yielded excellent nonlinear saturable absorption properties and was demonstrated to be suitable as an SA for an ultrafast solid-state laser. Stable mode-locked pulses of 325 fs were obtained at a central wavelength of 1032 nm with a repetition rate of 66.3 MHz. At pump power of 8.23 W the average output power was 1.78 W and the highest pulse energy reached 26.8 nJ with a peak power of 72.6 kW. Our work opens up a facile route for making reliable graphene SA in the mode-locking technique and also displays an exciting prospect in making low-cost and ultrafast lasers.
S C
SC
Xu
B Y
BY
Man
S Z
SZ
Jiang
D J
DJ
Feng
S B
SB
Gao
C S
CS
Chen
M
M
Liu
C
C
Yang
C
C
Zhang
D
D
Bi
F Y
FY
Liu
X
X
Meng