Lamb-dip-locked quantum cascade laser for comb-referenced IR absolute frequency measurements.
The frequency of a DFB quantum cascade laser (QCL) emitting at 4.3 microm has been long-term stabilized to the Lamb-dip center of a CO2 ro-vibrational transition by means of first-derivative locking to the saturated absorption signal. Thanks to the non-linear sum-frequency generation (SFG) process with a fiber-amplified Nd:YAG laser, the QCL mid-infrared (IR) radiation has been linked to an optical frequency-comb synthesizer (OFCS) and its absolute frequency counted with a kHz-level precision and an overall uncertainty of 75 kHz.
Borri
S
S
Istituto Nazionale di Ottica Applicata, CNR, Firenze, Italy.
Bartalini
S
S
Galli
I
I
Cancio
P
P
Giusfredi
G
G
Mazzotti
D
D
Castrillo
A
A
Gianfrani
L
L
De Natale
P
P
D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007259:Infrared Rays; D007834:Lasers; D008027:Light; D008962:Models, Theoretical; D012542:Scattering, Radiation; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*