Kilohertz-resolution spectroscopy of cold atoms with an optical frequency comb.
We have performed sub-Doppler spectroscopy on the narrow intercombination line of cold calcium atoms using the amplified output of a femtosecond laser frequency comb. Injection locking of a 657-nm diode laser with a femtosecond comb allows for two regimes of amplification, one in which many lines of the comb are amplified, and one where a single line is predominantly amplified. The output of the laser in both regimes was used to perform kilohertz-level spectroscopy. This experiment demonstrates the potential for high-resolution absolute-frequency spectroscopy over the entire spectrum of the frequency comb output using a single high-finesse optical reference cavity.
Fortier
T M
TM
Los Alamos National Laboratory, P-23 Physics Division, MS H803, Los Alamos, NM 87545, USA.
Coq
Y Le
YL
Stalnaker
J E
JE
Ortega
D
D
Diddams
S A
SA
Oates
C W
CW
Hollberg
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