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Reducing the linewidth of a diode laser below 30 Hz by stabilization to a reference cavity with finesse above 10^5

Adrien Schoof·Jan Gruenert·Stephan Ritter·Andreas Hemmerich
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Abstract

An extended cavity diode laser operating in the Littrow configuration emitting near 657 nm is stabilized via its injection current to a reference cavity with a finesse of more than 10^5 and a corresponding resonance linewidth of 14 kHz. The laser linewidth is reduced from a few MHz to a value below 30 Hz. The compact and robust setup appears ideal for a portable optical frequency standard using the Calcium intercombination line.

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Adrien Schoof, Jan Gruenert, Stephan Ritter, Andreas Hemmerich. 2001-09-22. Reducing the linewidth of a diode laser below 30 Hz by stabilization to a reference cavity with finesse above 10^5. https://doi.org/10.1364/ol.26.001562

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