A simple digital system for tuning and long-term frequency stabilisation of a CW Ti:Sapphire laser

TL;DR

This paper presents a simple, cost-effective digital system that stabilizes the frequency of a CW Ti:Sapphire laser over long periods using two confocal Fabry-Perot cavities, enhancing precision for high-resolution spectroscopy.

Contribution

The authors developed a novel digital stabilization system for Ti:Sapphire lasers that improves long-term frequency stability and is adaptable to arbitrary wavelengths.

Findings

Successfully stabilized laser frequency over extended periods.

Enhanced laser linewidth narrowing and stability.

Applied system in ultracold Rydberg atom spectroscopy.

Abstract

We have implemented a simple and cost-effective digital system for long-term frequency stabilisation and locking to an arbitrary wavelength of the single-frequency ring CW Ti:Sapphire laser. This system is built around two confocal Fabry-Perot cavities, one of which is used to narrow short-term line width of the laser and the other to improve long-term stability of the laser frequency. The second interferometer is also in the path of the radiation from an external-cavity diode laser stabilized to an atomic transition. Our system is an extension of a commercial Tekhnoscan laser lock. This system has been successfully used in experiments on high-resolution laser spectroscopy of ultracold Rydberg atoms.