Perspective on the next generation of ultra-low noise fiber supercontinuum sources and their emerging applications in spectroscopy, imaging, and ultrafast photonics

Anupamaa Rampur,Alexander M Heidt,Benoît Sierro,Mariusz Klimczak,Pascal Hänzi,Dirk-Mathys Spangenberg

doi:10.1063/5.0053436

Anupamaa Rampur, Alexander M Heidt + Show 4 more

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https://doi.org/10.1063/5.0053436

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Abstract

A new generation of ultrafast and low-noise supercontinuum (SC) sources is currently emerging, driven by the constantly increasing demands of spectroscopy, advanced microscopy, and ultrafast photonics applications for highly stable broadband coherent light sources. In this Perspective, we review recent progress enabled by advances in nonlinear optical fiber design, detail our view on the largely untapped potential for noise control in nonlinear fiber optics, and present the noise fingerprinting technique for measuring and visualizing the noise of SC sources with unprecedented detail. In our outlook, we highlight how these SC sources push the boundaries for many spectroscopy and imaging modalities and focus on their role in the development of ultrafast fiber lasers and frequency combs with ultra-low amplitude and phase noise operating in the 2 μm spectral region and beyond in the mid-IR.

Highlights

Optical spectroscopy and imaging using broadband coherent light sources that cover multiple molecular absorption bands and spectroscopic regimes have enabled fascinating insights into the world of molecular dynamics, revealing how greenhouse gases interact with pollutant particles or the unexpected complexities of water molecule vibrations1,2
Conventional SC sources employ fiber designs with single zero dispersion wavelength (ZDW) closely matched to the central wavelength of the pump pulses, which are injected in the region of anomalous group velocity dispersion (GVD) (Fig. 1 (a))
We review the motives behind the recent emergence of highly birefringent all-normal dispersion (ANDi) fibers as the key-enabling technology for the generation of ultra-low noise ultrafast SC sources20, and highlight how they are beginning to push the boundaries in several spectroscopy and imaging applications

Summary

INTRODUCTION

Optical spectroscopy and imaging using broadband coherent light sources that cover multiple molecular absorption bands and spectroscopic regimes have enabled fascinating insights into the world of molecular dynamics, revealing how greenhouse gases interact with pollutant particles or the unexpected complexities of water molecule vibrations. Pumping with mode-locked femtosecond lasers results in considerably more stable SC that preserve the temporal coherence of the pump pulses, and enable the formation of phase-stable broadband frequency combs or ultrashort pulses with only a few optical cycles duration. Pumping with mode-locked femtosecond lasers results in considerably more stable SC that preserve the temporal coherence of the pump pulses, and enable the formation of phase-stable broadband frequency combs or ultrashort pulses with only a few optical cycles duration11,12 Even in this regime the noise and temporal properties of SC sources are becoming increasingly limiting factors, which are closely linked to the design of the nonlinear fiber used to achieve spectral broadening. We further focus on their vital role in the development of ultra-low noise ultrafast fiber lasers and frequency combs operating in the 2μm spectral region and beyond in the mid-IR

ORIGIN OF SUPERCONTINUUM NOISE

NOISE CONTROL BY DISPERSION ENGINEERING

NOISE CONTROL BY DESIGNING FIBER GEOMETRY AND BIREFRINGENCE

APPLICATIONS AND FUTURE DIRECTIONS