Abstract
Doppler-free saturated absorption spectroscopy of
gases in hollow-core fiber (HCF)-based cells can be used for
realizing new compact, robust, and portable frequency standards.
In this paper, methods for cancelling interferences resulting
from the optical connections between standard fiber and HCF
and other factors such as varying coupling to HCF modes
are investigated. Laser power modulation with simultaneous
detection of ac and dc signal is used to separate saturated
absorption from interferences. In addition, a technique of
two piezoelectric stack actuators stretching the fiber at different
locations is described. The presented experimental results demonstrate
that 99% interference attenuation is readily attainable
with the techniques. Frequency comb-referenced measurement
of saturated acetylene absorption features near 1.54 μm, with
fiber length and power modulation, is presented. For comparison,
measurements and results of the same acetylene fiber, using
a system having pump and probe beams at mutually shifted
frequencies, are also given.
| Original language | English |
|---|---|
| Journal | I E E E Transactions on Instrumentation and Measurement |
| Volume | 64 |
| Issue number | 4 |
| Number of pages | 5 |
| ISSN | 0018-9456 |
| DOIs | |
| Publication status | Published - 2015 |
Keywords
- Frequency measurement standards
- Infrared spectra
- Interference cancellation
- Measurement techniques
- Metrology
- Optical fiber
- Spectroscopy