TY - JOUR

T1 - Single-Photon Level Dispersive Fourier Transform

T2 - Ultrasensitive Characterization of Noise-Driven Nonlinear Dynamics

AU - Sader, Lynn

AU - Bose, Surajit

AU - Kashi, Anahita Khodadad

AU - Boussafa, Yassin

AU - Haldar, Raktim

AU - Dauliat, Romain

AU - Roy, Philippe

AU - Fabert, Marc

AU - Tonello, Alessandro

AU - Couderc, Vincent

AU - Kues, Michael

AU - Wetzel, Benjamin

N1 - Funding Information: This work has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 950618 (STREAMLINE project) and No. 947603 (QFreC project), from the French Agence Nationale de la Recherche (ANR) through the OPTIMAL project (ANR-20-CE30-0004), from the German Federal Ministry of Education and Research within the project PQuMAL and the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy within the Cluster of Excellence PhoenixD (EXC 2122, Project ID 390833453). L.S., Y.B., and B.W. further acknowledge the support of the Conseil Régional Nouvelle-Aquitaine (SCIR & SPINAL projects). R.H. acknowledges the financial support provided by the Alexander von Humboldt Stiftung to conduct the research.

PY - 2023/11/15

Y1 - 2023/11/15

N2 - Dispersive Fourier transform is a characterization technique that allows directly extracting an optical spectrum from a time domain signal, thus providing access to real-time characterization of the signal spectrum. However, these techniques suffer from sensitivity and dynamic range limitations, hampering their use for special applications in, e.g., high-contrast characterizations and sensing. Here, we report on a novel approach to dispersive Fourier transform-based characterization using single-photon detectors. In particular, we experimentally develop this approach by leveraging mutual information analysis for signal processing and hold a performance comparison with standard dispersive Fourier transform detection and statistical tools. We apply the comparison to the analysis of noise-driven nonlinear dynamics arising from well-known modulation instability processes. We demonstrate that with this dispersive Fourier transform approach, mutual information metrics allow for successfully gaining insight into the fluctuations associated with modulation instability-induced spectral broadening, providing qualitatively similar signatures compared to ultrafast photodetector-based dispersive Fourier transform but with improved signal quality and spectral resolution (down to 53 pm). The technique presents an intrinsically unlimited dynamic range and is extremely sensitive, with a sensitivity reaching below the femtowatt (typically 4 orders of magnitude better than ultrafast dispersive Fourier transform detection). We show that this method can not only be implemented to gain insight into noise-driven (spontaneous) frequency conversion processes but also be leveraged to characterize incoherent dynamics seeded by weak coherent optical fields.

AB - Dispersive Fourier transform is a characterization technique that allows directly extracting an optical spectrum from a time domain signal, thus providing access to real-time characterization of the signal spectrum. However, these techniques suffer from sensitivity and dynamic range limitations, hampering their use for special applications in, e.g., high-contrast characterizations and sensing. Here, we report on a novel approach to dispersive Fourier transform-based characterization using single-photon detectors. In particular, we experimentally develop this approach by leveraging mutual information analysis for signal processing and hold a performance comparison with standard dispersive Fourier transform detection and statistical tools. We apply the comparison to the analysis of noise-driven nonlinear dynamics arising from well-known modulation instability processes. We demonstrate that with this dispersive Fourier transform approach, mutual information metrics allow for successfully gaining insight into the fluctuations associated with modulation instability-induced spectral broadening, providing qualitatively similar signatures compared to ultrafast photodetector-based dispersive Fourier transform but with improved signal quality and spectral resolution (down to 53 pm). The technique presents an intrinsically unlimited dynamic range and is extremely sensitive, with a sensitivity reaching below the femtowatt (typically 4 orders of magnitude better than ultrafast dispersive Fourier transform detection). We show that this method can not only be implemented to gain insight into noise-driven (spontaneous) frequency conversion processes but also be leveraged to characterize incoherent dynamics seeded by weak coherent optical fields.

KW - fiber optics

KW - modulation instability

KW - nonlinear photonics

KW - real-time characterization techniques

KW - spectral correlation

UR - http://www.scopus.com/inward/record.url?scp=85178064589&partnerID=8YFLogxK

U2 - 10.1021/acsphotonics.3c00711

DO - 10.1021/acsphotonics.3c00711

M3 - Article

AN - SCOPUS:85178064589

VL - 10

SP - 3915

EP - 3928

JO - ACS PHOTONICS

JF - ACS PHOTONICS

SN - 2330-4022

IS - 11

ER -