Near-infrared nanospectroscopy using a low-noise supercontinuum source

Kaltenecker, Korbinian J.; Rao, Shreesha D. S.; Rasmussen, Mattias; Lassen, Henrik B.; Kelleher, Edmund J. R.; Krauss, Enno; Hecht, Bert; Mortensen, N. Asger; Gruener-Nielsen, Lars; Markos, Christos; Bang, Ole; Stenger, Nicolas und Jepsen, Peter Uhd (2021): Near-infrared nanospectroscopy using a low-noise supercontinuum source. In: Apl Photonics, Bd. 6, Nr. 6, 66106

Abstract

Unlocking the true potential of optical spectroscopy on the nanoscale requires development of stable and low-noise laser sources. Here, we have developed a low-noise supercontinuum (SC) source based on an all-normal dispersion fiber pumped by a femtosecond fiber laser and demonstrate high resolution, spectrally resolved near-field measurements in the near-infrared (NIR) region. Specifically, we explore the reduced-noise requirements for aperture-less scattering-type scanning near-field optical microscopy (s-SNOM), including inherent pulse-to-pulse fluctuation of the SC. We use our SC light source to demonstrate the first NIR, spectrally resolved s-SNOM measurement, a situation where state-of-the-art commercial SC sources are too noisy to be useful. We map the propagation of surface plasmon polariton (SPP) waves on monocrystalline gold platelets in the wavelength region of 1.34-1.75 mu m in a single measurement, thereby characterizing experimentally the dispersion curve of the SPP in the NIR. Our results represent a technological breakthrough that has the potential to enable a wide range of new applications of low-noise SC sources in near-field studies.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 2378-0967
• Sprache: Englisch