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Phase correlation of laser waves with arbitrary frequency spacing

A. F. Huss·R. Lammegger·C. Neureiter·E. A. Korsunsky·L. Windholz
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Abstract

The theoretically predicted correlation of laser phase fluctuations in Lambda-type interaction schemes is experimentally demonstrated. We show, that the mechanism of correlation in a Lambda scheme is restricted to high frequency noise components, whereas in a double-$Λ$ scheme, due to the laser phase locking in closed-loop interaction, it extends to all noise frequencies. In this case the correlation is weakly sensitive to coherence losses. Thus the double-Lambda scheme can be used to correlate e.m. fields with carrier frequency differences beyond the GHz regime.

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A. F. Huss, R. Lammegger, C. Neureiter, E. A. Korsunsky, L. Windholz. 2004-04-20. Phase correlation of laser waves with arbitrary frequency spacing. https://doi.org/10.1103/physrevlett.93.223601

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