Surface Enhanced Spectroscopy; Plasmonics; Molecular analytics
le Feber Boris, Prins Ferry, De Leo Eva, Rabouw Freddy T., Norris David J. (2018), Colloidal-Quantum-Dot Ring Lasers with Active Color Control, in Nano Letters
, 18(2), 1028-1034.
De Leo Eva, Cocina Ario, Tiwari Preksha, Poulikakos Lisa V., Marqués-Gallego Patricia, le Feber Boris, Norris David J., Prins Ferry (2017), Polarization Multiplexing of Fluorescent Emission Using Multiresonant Plasmonic Antennas, in ACS Nano
, 11(12), 12167-12173.
Prins Ferry, Kim David K., Cui Jian, De Leo Eva, Spiegel Leo L., McPeak Kevin M., Norris David J. (2017), Direct Patterning of Colloidal Quantum-Dot Thin Films for Enhanced and Spectrally Selective Out-Coupling of Emission, in Nano Letters
, 17(3), 1319-1325.
Surface enhanced spectroscopy provides many orders of magnitude improvements in the detection efficiency of molecular vibrational signatures. However, conventional plasmonic surface enhancement employs only single resonant enhancement, providing optimal enhancement of at most a single optical transition (i.e. excitation or emission/scattering). Dual-resonant enhancement can be used to overcome this issue, but the broader availability of this technique has been hampered by limitations in the flexibility and versatility of existing platforms. Moreover, applications of dual-resonant enhancement beyond Raman spectroscopy have been largely unexplored. Consequently, present-day strategies do not exploit the full strength that surface enhancement offers. Here, I propose to create a versatile plasmonic platform in which widely tunable multiple resonances will allow for simultaneous optimization of excitation, emission and scattering transitions. Central in my approach will be the use of concentric gratings, most prominently the circular metallic Bull’s Eye. Metallic Bull’s Eyes possess sharp resonances with high directionality that can be tuned across wide spectral ranges through simple variations in the grating periodicity. The results of this project form a prerequisite for wider applicability of dual resonant surface enhancement in both spectroscopy and photonic devices. Because of their straightforward, yet highly tunable structure, the proposed plasmonic surfaces will provide a versatility not found in today's conventional surface enhancement platforms.