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Updated: May 8, 2026
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In-situ Tapering of Chalcogenide Fiber for Mid-infrared Supercontinuum Generation
Published on: May 27, 2013
Real time noise and wavelength correlations in octave-spanning supercontinuum generation
T Godin1, B Wetzel, T Sylvestre
1Institut FEMTO-ST, UMR 6174 CNRS-Université de Franche-Comté, 25030 Besançon, France. thomas.godin@femto-st.fr
Optics Express
|August 14, 2013
Summary
Dispersive Fourier transformation effectively measures spectral instabilities in femtosecond supercontinuum generation. This technique reveals hidden spectral component interactions, crucial for understanding noise in supercontinuum development.
Area of Science:
- Nonlinear Optics
- Ultrafast Laser Science
Background:
- Supercontinuum generation is vital for spectroscopy and optical frequency combs.
- Characterizing spectral instabilities is key to controlling supercontinuum properties.
- Existing methods struggle to capture complex spectral dynamics in unstable regimes.
Purpose of the Study:
- To employ dispersive Fourier transformation (DFT) for analyzing shot-to-shot spectral instabilities in femtosecond supercontinuum generation.
- To investigate both the initial phase of supercontinuum formation and highly unstable, octave-spanning bandwidths.
- To identify interactions between distinct spectral components using wavelength correlation maps.
Main Methods:
- Utilizing dispersive Fourier transformation (DFT) for high-resolution spectral measurements.
- Analyzing spectral noise and instabilities on a shot-to-shot basis.
- Employing wavelength correlation maps to uncover hidden spectral interactions.
- Validating experimental findings through numerical simulations.
Main Results:
- DFT successfully measured spectral instabilities during femtosecond supercontinuum generation.
- Distinct dispersive wave generation and octave-spanning unstable regimes were characterized.
- Wavelength correlation maps revealed interactions not visible in standard measurements.
- Numerical simulations supported the experimental observations.
Conclusions:
- Dispersive Fourier transformation offers significant advantages for studying spectral noise in supercontinuum generation.
- The technique provides unprecedented insight into the dynamics of unstable supercontinua.
- DFT is a powerful tool for advancing the understanding and control of ultrafast light sources.
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