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arXiv · 1507.08519

Sub-kHz linewidth narrowing of a mid-infrared OPO idler frequency by direct cavity stabilization

I. Ricciardi·S. Mosca·M. Parisi·P. Maddaloni·L. Santamaria·P. De Natale·M. De Rosa
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Abstract

We stabilize the idler frequency of a singly-resonant optical parametric oscillator directly to the resonance of a mid-infrared Fabry-P\'erot reference cavity. This is accomplished by the Pound-Drever-Hall locking scheme, controlling either the pump laser or the resonant signal frequency. A residual relative frequency noise power spectral density below 10$^3$ Hz$^2$/Hz is reached, with a Gaussian linewidth of 920 Hz over 100 ms, which demonstrates the potential for reaching spectral purity down to the Hz level by locking the optical parametric oscillator against a mid-infrared cavity with state-of-the-art superior performance.

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I. Ricciardi, S. Mosca, M. Parisi, P. Maddaloni, L. Santamaria, P. De Natale, M. De Rosa. 2015-07-30. Sub-kHz linewidth narrowing of a mid-infrared OPO idler frequency by direct cavity stabilization. https://doi.org/10.1364/ol.40.004743

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