Toward a 1.54 μm frequency standard with Er-Yb (¹³C 2 H 2 )

Abstract

A novel Er-Yb:glass quasi-monolithic diode-pumped laser has been developed to realize a high-accuracy frequency standard at 1.54 µm based on saturated absorption of isotopic acetylene. This compact oscillator shows low amplitude-and frequency-noise, wide wavelength tunability (~20 nm), and continuous output power in excess of 20 mW with excellent linear polarization (~30 dB extinction ratio). Employing this laser source sub-Doppler spectroscopy of the acetylene around 1.54 µm has been performed. To obtain the necessary saturation intensity (~3.5 W/mm 2 ), the absorbing sample is placed inside a Fabry-Perot cavity with a Finesse of ~150. The dispersion signal of the sub-Doppler resonance, useful to stabilize the laser frequency, has been obtained by dithering the Fabry-Perot piezo and employing a lock-in detection scheme.

High-resolution spectroscopy of the /sup 39/K transitions at 770 nm and /sup 13/C/sub 2/H/sub 2/ saturated lines by a solid-state laser at 1.54 μm: toward an accurate frequency standard in the optical communication band

“…In our experiments, in order to obtain a saturated absorption signal, we used a Brewster-window quartz cell filled with C H at a pressure of 4 Pa placed inside a Fabry-Perot cavity [12]. This is a passive plano-spherical resonator, 30 cm long, with a 2.5-MHz linewidth and a finesse of 200.…”

“…High-resolution spectroscopy of both atomic and molecular transitions is here discussed toward the realization of a frequency standard in the 1.5-m optical band. In this work, we first report on a novel Er-Yb: glass microlaser [12], with significantly improved stability and reliability performance, particularly suitable for absolute frequency stabilization experiments. The main novelties are related to a very compact design of the laser cavity, with a massive and hermetically sealed-off laser structure and to the use of a fiber-coupled diode laser pumping.…”

Amplitude and frequency stabilized solid-state lasers in the near infrared

“…The threshold reduction arises from an effective ytterbium to erbium transfer mechanism of the excitation energy. Er-Yb:glass lasers, as the ones used in our experiments are thoroughly described in [49][50][51]. The maximum laser output power, largely varying from one experiment to another, typically ranges between 10 mW and 100 mW and is mainly limited from thermal damage to the glass active medium.…”