| Author(s): |
Esther Baumann; Fabrizio R. Giorgetta; Ian R. Coddington; William C. Swann; Nathan R. Newbury; |
| Title: |
Spectroscopy with a coherent dual frequency comb interferometer at 3.4 µm |
| Published: |
August 01, 2010 |
| Abstract: |
A coherent dual fiber-comb spectrometer centered at 1.5 µm wavelengths is transferred to 3.4 µm by difference-frequency generation with a 1064 nm cw laser. It is shown that the residual linewidth between the comb teeth at 3.4 µm is resolution-limited to 200 mHz; such narrow linewidths can enable coherent dual-comb spectroscopy at high-precision and signal-to-noise ratio. We then discuss different interferometric configurations for coherent dual-comb spectroscopy. We find that a two branch interferometric setup is appropriate to measure both the magnitude and phase spectrum of purely Doppler broadened absorption lines. An initial measurement of methane lines in the nu3 band P-branch with a resolution of 114 MHz is demonstrated. |
| Proceedings: |
SPIE Optical Engineering + Applications:Interferometry XV: Techniques and Analysis |
| Volume: |
7790 |
| Pages: |
8 pp. |
| Location: |
San Diego, CA |
| Dates: |
August 1-5, 2010 |
| Keywords: |
Frequency combs, Mid-IR, Molecular spectroscopy |
| Research Areas: |
Optoelectronics, Molecular Spectroscopy |
| PDF version: |
 Click here to retrieve PDF version of paper (1MB) |
