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Frequency-comb-based multidimensional coherent spectroscopy is a powerful optical method for studying nonlinear optical properties of samples with narrow resonances. It enables the measurement of multidimensional coherent spectra rapidly and with high spectral resolution. However, for some samples (especially cold atoms and molecules) the dephasing times are longer than the repetition periods of the excitation lasers and hence the nonlinear signals generated in the sample by the subsequent laser pulses will interfere with each other. Here we investigate this behavior and show its effect on multidimensional coherent spectra by solving the optical Bloch equations. *The material is based upon work supported by the National Science Foundation under Grant No. [1904704]
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Strategies for phase matching control in a multidimensional Floquet state spectroscopy
Floquet state spectroscopy is an optical analogue of multiple quantum coherence nuclear magnetic resonance (MQC-NMR). Tunable ultrafast excitation pulses resonantly excite multiple states in a sample to form the Floquet state. The Floquet state emits multiple coherent beams at frequencies and in directions that conserve energy and momenta. The different output beams differ in the time ordering and coherences created by the excitation beams. They correspond to the different methodologies in the NMR family. Isolating a specific beam and monitoring the output intensity as a function of excitation frequencies creates multidimensional spectra containing cross-peaks between coupled states. The frequency range of the multidimensional spectra is limited by phase matching constraints. This paper presents a new, to the best of our knowledge, active phase matching strategy that increases the versatility of multidimensional Floquet state spectroscopy through both longer sample path lengths and larger spectral ranges.
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- Award ID(s):
- 2203290
- PAR ID:
- 10487563
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Letters
- Volume:
- 49
- Issue:
- 3
- ISSN:
- 0146-9592; OPLEDP
- Format(s):
- Medium: X Size: Article No. 610
- Size(s):
- Article No. 610
- Sponsoring Org:
- National Science Foundation
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