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Related Experiment Video

Updated: May 13, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

Background suppression in synthesized pulse waveform by feedback control optimization for flatly broadened

Ken Kashiwagi¹, Hiroyuki Ishizu, Yuichiro Kodama

¹Department of Electrical and Electronic Engineering, Graduate School of Engineering, Tokyo University of Agriculture and Technology, 2-24-16, Nakacho, Koganei, Tokyo 184-8588, Japan. kkash@cc.tuat.ac.jp

|March 14, 2013

Summary

We developed a method using adaptive pulse shaping to suppress background noise in synthesized pulses for supercontinuum (SC) generation. This technique significantly improves the flatness of the SC spectrum, crucial for advanced optical applications.

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Last Updated: May 13, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

Area of Science:

Nonlinear Optics
Quantum Optics
Laser Physics

Background:

Supercontinuum (SC) generation is vital for various applications, but spectral flatness is often limited by background components.
Achieving a flat SC spectrum requires precise control over the pump pulse characteristics.

Purpose of the Study:

To demonstrate a novel method for background component suppression in synthesized pulses.
To enhance the flatness of broadened supercontinuum generation using adaptive pulse shaping.

Main Methods:

Employed adaptive pulse shaping in the frequency domain with two combined fitness functions.
Utilized feedback-controlled pulse shaping to optimize pump pulse characteristics.
Investigated the impact of phase spectra control on spectral peak suppression.

Main Results:

Achieved a 26 dB contrast between pulse center and background in the auto-correlation trace.
Suppressed the spectral peak of the SC at the pump wavelength by 5 dB.
Simulations indicated that phase spectra control within ± π/100 rad is necessary for significant spectral peak reduction.

Conclusions:

Adaptive pulse shaping is essential for improving SC flatness due to stringent phase mismatch tolerances.
The demonstrated method offers a viable approach for generating flat supercontinuum spectra.
Precise control over synthesized pulse properties is key to optimizing SC generation.