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arXiv · 1708.05728

Linear and Nonlinear Time- and Frequency-Domain Spectroscopy with Multiple Frequency Combs

Kochise Bennett·Jeremy Rouxel·Shaul Mukamel
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Abstract

Two techniques that employ equally spaced trains of optical pulses to map an optical high frequency into a low frequency modulation of the signal that can be detected in real time are compared. The development of phase-stable optical frequency combs has opened up new avenues to metrology and spectroscopy. The ability to generate a series of frequency spikes with precisely controlled separation permits a fast, highly accurate sampling of the material response. Recently, pairs of frequency combs with slightly different repetition rates have been utilized to down-convert material susceptibilities from the optical to microwave regime where they can be recorded in real time. We show how this one-dimensional dual comb technique can be extended to multiple dimensions by using several combs. We demonstrate how nonlinear susceptibilities can be quickly acquired using this technique. In a second class of techniques, sequences of ultrafast mode locked laser pulses are used to recover pathways of interactions contributing to nonlinear susceptibilities by using a photo-acoustic modulation varying along the sequences. We show that these techniques can be viewed as a time-domain analogue of the multiple frequency comb scheme. %We compare the two techniques: in both, an optical high frequency is mapped into a low frequency modulation of the signal that can be detected in real time.

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Kochise Bennett, Jeremy Rouxel, Shaul Mukamel. 2017-08-18. Linear and Nonlinear Time- and Frequency-Domain Spectroscopy with Multiple Frequency Combs. https://arxiv.org/abs/1708.05728

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