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arXiv · 1608.08102

Cavity-enhanced ultrafast two-dimensional spectroscopy using higher-order modes

Thomas K. Allison
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Abstract

We describe methods using frequency combs and optical resonators for recording two-dimensional (2D) ultrafast spectroscopy signals with high sensitivity. By coupling multiple frequency combs to higher-order modes of one or more optical cavities, background-free, cavity-enhanced 2D spectroscopy signals are naturally generated via phase cycling. As in cavity-enhanced ultrafast transient absorption spectroscopy (CE-TAS), the signal to noise is enhanced by a factor proportional to the cavity finesse squared, so even using cavities of modest finesse, a very high sensitivity is expected, enabling ultrafast 2D spectroscopy experiments in dilute molecular beams.

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Thomas K. Allison. 2016-08-29. Cavity-enhanced ultrafast two-dimensional spectroscopy using higher-order modes. https://doi.org/10.1088/1361-6455%2F50%2F4%2F044004

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