We describe a successful effort to produce a laser comb around 1.55 $\mu$m in
the astronomical H band using a method based on a line-referenced,
electro-optical-modulation frequency comb. We discuss the experimental setup,
laboratory results, and proof of concept demonstrations at the NASA Infrared
Telescope Facility (IRTF) and the Keck-II telescope. The laser comb has a
demonstrated stability of $<$ 200 kHz, corresponding to a Doppler precision of
~0.3 m/s. This technology, when coupled with a high spectral resolution
spectrograph, offers the promise of $<$1 m/s radial velocity precision suitable
for the detection of Earth-sized planets in the habitable zones of cool M-type
stars

C. Beichman

E. C. Martin

E. Furlan

G. Doppmann

G. Vasisht

G. Ycas

J. Gagne

J. Li

J. Sandhu

K. Vahala

M. Bottom

M. P. Fitzgerald

P. Chen

P. Gao

P. Plavchan

S. Diddams

S. Leifer

X. Yi

Nature Communications

English

arXiv

AbstractAn important technique for discovering and characterizing planets beyond our solar system relies upon measurement of weak Doppler shifts in the spectra of host stars induced by the influence of orbiting planets. A recent advance has been the introduction of optical frequency combs as frequency references. Frequency combs produce a series of equally spaced reference frequencies and they offer extreme accuracy and spectral grasp that can potentially revolutionize exoplanet detection. Here we demonstrate a laser frequency comb using an alternate comb generation method based on electro-optical modulation, with the comb centre wavelength stabilized to a molecular or atomic reference. In contrast to mode-locked combs, the line spacing is readily resolvable using typical astronomical grating spectrographs. Built using commercial off-the-shelf components, the instrument is relatively simple and reliable. Proof of concept experiments operated at near-infrared wavelengths were carried out at the NASA Infrared Telescope Facility and the Keck-II telescope.</jats:p

Crossref

Demonstration of a near-IR line-referenced electro-optical laser frequency comb for precision radial velocity measurements in astronomy

An important technique for discovering and characterizing planets beyond our solar system relies upon measurement of weak Doppler shifts in the spectra of host stars induced by the influence of orbiting planets. A recent advance has been the introduction of optical frequency combs as frequency references. Frequency combs produce a series of equally spaced reference frequencies and they offer extreme accuracy and spectral grasp that can potentially revolutionize exoplanet detection. Here we demonstrate a laser frequency comb using an alternate comb generation method based on electro-optical modulation, with the comb centre wavelength stabilized to a molecular or atomic reference. In contrast to mode-locked combs, the line spacing is readily resolvable using typical astronomical grating spectrographs. Built using commercial off-the-shelf components, the instrument is relatively simple and reliable. Proof of concept experiments operated at near-infrared wavelengths were carried out at the NASA Infrared Telescope Facility and the Keck-II telescope

Yi, X.

Vahala, Kerry J.

Diddams, Scott A.

Ycas, Gabriel G.

Plavchan, Peter

Leifer, S. D.

Sandhu, J.

Vasisht, Gautam

Chen, P.

Gao, J.

Furlan, E.

Bottom, M.

Martin, E. C.

Fitzgerald, Michael P.

Doppmann, Greg W.

Beichman, C.

Caltech Authors - Main

Yi, X

Vahala, K

Li, J

Diddams, S

Ycas, G

Plavchan, P

Leifer, S

Sandhu, J

Vasisht, G

Chen, P

Gao, P

Gagne, J

Furlan, E

Bottom, M

Martin, EC

Fitzgerald, MP

Doppmann, G

Beichman, C

eScholarship - University of California

https://authors.library.caltech.edu/64022/1/ncomms10436.pdf