Articolele autorului Corneliu Catalin Neacsu
Link la profilul stiintific al lui Corneliu Catalin Neacsu

Tip-enhanced Raman imaging and spectroscopy: sensitivity, symmetry and selection rules

The fundamental mechanisms of tip-enhanced Raman spectroscopy (TERS) have been investigated, including the role of the plasmonic excitation of the metallic tips, the nature of the optical tip-sample coupling, and the resulting local-field enhancement and confinement responsible for ultrahigh resolution imaging down to just several nanometers. Criteria for the distinction of near-field signature from far-field imaging artifacts are addressed. TERS

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Light Confinement at Ultrasharp Metallic Tips

In this article, two alternative experimental strategies for reaching light confinement at metallic nanotips are discussed. The first approach utilizes optical field enhancement to localize nonlinear optical signals at the tip end. The second approach employs surface plasmon polaritons propagating coherently along the tip shaft and converging at its apex.

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Absorption, luminescence, and Raman spectroscopic properties of thin films of benzo-annelated metal-free

Thin film properties of the set of metal-free linearly benzo-annelated porphyrazines, tetra(tert-butyl)porphyrazine (tBu-TAPH2), tetra(tert-butyl)phthalocyanine (tBu-PcH2), tetra(tert-butyl)naphthalocyanine (tBu-NpH2), and octaphenyltetraanthraporphyrazine (AnH2) were studied by laser excitation using micro-Raman and -luminescence spectroscopy. With the exception of tBu-TAPH2 all compounds are characterized by a broad absorption pattern mainly due

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Grating-coupling of surface plasmons onto metallic tips: A nanoconfined light source

We describe and demonstrate a new nanometer-scale broadband light source. It is based on the grating-coupled excitation of surface plasmon polaritons (SPPs) on the shaft of a sharp conical metal taper with a tip radius of few tens of nanometers. Far-field excitation of linear nanoslit gratings results in the resonant generation of SPPs traveling over more than 10 microm to the tip apex and converging to an intense radiative local light spot. Such

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Reply to Comment on $^Scanning-probe Raman spectroscopy with single-molecule sensitivity$^
Resonant-plasmon field enhancement from asymmetrically illuminated conical metallic-probe tips
Scanning-probe Raman spectroscopy with single-molecule sensitivity
Precision lifetime measurement of the $2p ^2P_3/2$ level for Li-like Ni by beam-foil spectroscopy
Plasmonic light scattering from nanoscopic metal tips
Second-harmonic generation from nanoscopic metal tips: Symmetry selection rules for single asymmetric nanostructures