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arXiv · 1212.6266

Injection-locking of violet laser diodes with a 3.2GHz offset frequency for driving Raman transitions in 43Ca+

B. C. Keitch·N. R. Thomas·D. M. Lucas
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Abstract

Two cw single-mode violet (397nm) diode lasers are locked to a single external-cavity master diode laser by optical injection locking. A double-pass 1.6GHz acousto-optic modulator is used to provide a 3.2GHz offset frequency between the two slave lasers. We achieve up to 20mW usable output in each slave beam, with as little as 25 μW of injection power at room temperature. An optical heterodyne measurement of the beat note between the two slave beams gives a linewidth of <=10Hz at 3.2GHz. We also estimate the free-running linewidth of the master laser to be approximately 3MHz, by optical heterodyning with a similar device.

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B. C. Keitch, N. R. Thomas, D. M. Lucas. 2012-12-26. Injection-locking of violet laser diodes with a 3.2GHz offset frequency for driving Raman transitions in 43Ca+. https://doi.org/10.1364/ol.38.000830

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