ORS

The ORS-FS-XTAL option extension allows to achieve the ultimate short-term frequency stability for clock applications by employing highly reflective crystalline coatings used on fused silica substrates as cavity mirrors, thus strongly reducing the thermal noise floor. In addition, the intracavity power is actively stabilized with a feedback to an AOM.

Available only for the ORS for selected wavelengths above 900 nm.

The EOM Sideband Lock Package provides a broadly-tunable, ultrastable laser output. Here, an electro-optic modulator (EOM) is used to generate sidebands on the laser light that is sent to the cavity. Subsequently, a modulation sideband is coupled into the reference cavity, while the carrier is used as a frequency tunable, ultrastable user output. A tuning of up to half of the free spectral range (±0.5 × FSR) is possible.

The ORS-FNC extension package enables the transmission of sub-Hz linewidth laser light through active phase-noise compensation of the ultrastable laser output. The ORS-FNC interferometrically detects the phase noise induced by temperature variations and vibrations in the fiber and actively compensates this using a phase-locked loop and an AOM as actuator. The residual noise contribution of such a stabilized fiber link is well below the frequency stability of the ORS.

For the simultaneous stabilization of multiple lasers to the same reference cavity, custom coating designs and cavity mirrors which are highly reflective at two or multiple wavelengths can be tailored to your application.

The ORS-SHG extension includes a frequency doubling unit which is integrated into your system with a free-space or fiber-coupled output. This allows to build an ultrastable laser system at longer wavelengths by frequency doubling its output, which can be advantageous in many applications (e.g., at 1397 nm for the Strontium clock transition at 698 nm).

The ORS-HP options allow to amplify the standard 10 mW output signal of the ultrastable laser to the power level required for your application (e.g. for achieving > 1 W at 729 nm for Ca⁺ experiments). The amplifiers are placed within the frequency stabilization servo loop and thus merely affect the system’s stability.

The ORS-DDRIFT package is designed to compensate the inevitable linear drift of the aging reference cavity. It includes a direct digital frequency synthesizer (DDS), a high-power RF amplifier, an acousto-optic modulator (AOM) and a software-module. An adjustable linear frequency ramp is programmed to the DDS and applied to the system’s acousto-optic modulator to compensate the linear drift.

The ORS-DSRV Package provides a digital servo interface to stabilize the frequency of the ultrastable laser to a user-given target (e.g., a clock transition). It includes a direct digital frequency synthesizer (DDS), a high-power RF amplifier, an acousto-optic modulator (AOM) and a software-module. The user must supply a frequency error reading and the SYNCRO control platform integrates it and feeds it back to an AOM in order to stabilize the laser to the external reference.

Comparison of the fractional frequency stability of the standard ORS (1542 nm) against an ORS with crystalline coatings (ORS-FS-XTAL, 1542 nm)

ORS with ORS-FS-XTAL Phase noise (1542nm)