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Phase stability between pulse pairs defining Fourier-transform time delays can limit resolution and complicates development and adoption of multidimensional coherent spectroscopies. We demonstrate a data processing procedure to correct the long-term phase drift of the nonlinear signal during two-dimensional (2D) experiments based on the relative phase between scattered excitation pulses and a global phasing procedure to generate fully absorptive 2D electronic spectra of wafer-scale monolayer MoS2. Our correction results in a ∼30-fold increase in effective long-term signal phase stability, from ∼λ/2 to ∼λ/70 with negligible extra experimental time and no additional optical components. This scatter-based drift correction should be applicable to other interferometric techniques as well, significantly lowering the practical experimental requirements for this class of measurements.
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Frequency-comb-based multidimensional coherent spectroscopy of systems with long-lived excited states*
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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- Award ID(s):
- 1904704
- PAR ID:
- 10470215
- Publisher / Repository:
- American Physical Society
- Date Published:
- Format(s):
- Medium: X
- Location:
- APS March Meeting
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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- The DOI is not currently available.
