Oxide mediated spectral shifting in aluminum resonant optical antennas.

As a key feature among metals showing good plasmonic behavior, aluminum extends the spectrum of achievable plasmon resonances of optical antennas into the deep ultraviolet. Due to degradation, a native oxide layer gives rise to a metal-core/oxide-shell nanoparticle and influences the spectral resonance peak position. In this work, we examine the role of the underlying processes by applying numerical nanoantenna models that are experimentally not feasible.

Sensitivity improvement in fluorescence-based particle detection.

Microfluidic flow cytometers are highly interesting candidates for biomedical point-of-care applications. However, the sensitivity, reliability, and throughput of these systems must be improved to provide the full functionality of established flow cytometric systems. One proposed method to improve fluorescence detection systems is to use spatial modulation techniques.

Linear and nonlinear optical characterization of aluminum nanoantennas.

We experimentally determine the order of multiphoton induced luminescence of aluminum nanoantennas fabricated on a nonconductive substrate using electron-beam lithography to be 2.11 (±0.10).

Gold nanoantenna resonance diagnostics via transversal particle plasmon luminescence.

We perform two-photon excitation confocal experiments on coupled gold nanoantennas and observe time-integrated luminescence spectra that match plasmonic mode emission in the far-field. We show that the transversal particle plasmon mode can be excited, using excitation light that is cross-polarized with respect to the gold luminescence signal and therefore oriented along the long axis of the dipole gold antenna. We provide evidence for losses in polarization information from the excitation channel to the luminescence response due to the nature of the energy and momentum transfer.