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arXiv · 1702.02957

A versatile, high-power 460nm laser system for Rydberg excitation of ultracold potassium

Alda Arias·Stephan Helmrich·Christoph Schweiger·Lynton Ardizzone·Graham Lochead·Shannon Whitlock
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Abstract

We present a versatile laser system which provides more than 1.5W of narrowband light, tunable in the range from 455-463 nm. It consists of a commercial Titanium-Sapphire laser which is frequency doubled using resonant cavity second harmonic generation and stabilized to an external reference cavity. We demonstrate a wide wavelength tuning range combined with a narrow linewidth and low intensity noise. This laser system is ideally suited for atomic physics experiments such as two-photon excitation of Rydberg states of potassium atoms with principal quantum numbers n > 18. To demonstrate this we perform two-photon spectroscopy on ultracold potassium gases in which we observe an electromagnetically induced transparency resonance corresponding to the 35s1/2 state and verify the long-term stability of the laser system. Additionally, by performing spectroscopy in a magneto-optical trap we observe strong loss features corresponding to the excitation of s, p, d and higher-l states accessible due to a small electric Field.

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Alda Arias, Stephan Helmrich, Christoph Schweiger, Lynton Ardizzone, Graham Lochead, Shannon Whitlock. 2017-02-09. A versatile, high-power 460nm laser system for Rydberg excitation of ultracold potassium. https://doi.org/10.1364/oe.25.014829

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