Addressing Field-Enhanced Molecular Spectroscopy in Extreme Nanocavities

Presenter: Professor Javier Aizpurua, University of the Basque Country (UPV/EHU)

A plasmonic nanogap is a superb configuration to explore the interplay between light and matter. Light scattered off, or emitted from a nanogap carries the information of the surrounding electromagnetic environment with it. This situation becomes even more appealing when a single molecule is located in such a plasmonic cavity or in its proximity, with the molecule playing an active role either in the electromagnetic coupling with the nanocavity, or even participating in processes of charge injection and transfer, as revealed through cutting-edge molecular spectroscopy. In this talk, the process of interaction between a molecular emitter and a nanocavity will be addressed by means of different theoretical frameworks which involve aspects of condensed matter physics, quantum chemistry, and cavity-quantum electrodynamics. A battery of methodologies to address the dynamics of electrons photo-emitted from nanogaps, ultra resolution in atomic- scale photoluminescence, or non-linear regimes in molecular optomechanics will be described, and many of the theoretical insights obtained will be interpreted in the context of state-of-the-art experimental results in nanocavity-enhanced molecular spectroscopy.

References

[1] A. Babaze, R. Esteban, A. G. Borisov, and J. Aizpurua, Nano Lett. 21, 8466-8473 (2021).
[2] A. Roslawska, T. Neuman, B. Doppagne, A. G. Borisov, M. Romeo, F. Scheurer, J. Aizpurua, and G. Schull, Phys. Rev. X. 12, 011012 (2022).
[3] R. Esteban, J. J. Baumberg, and J. Aizpurua, Acc. Chem. Res. 55, 1889-1899 (2022).

Javier Aizpurua

Javier Aizpurua is an Ikerbasque Research Professor at Donostia International Physics Center (DIPC) in San Sebastian, Spain, where he leads the “Theory of Nanophotonics Group” devoted to the study of the interaction of light and nanostructured materials. Aizpurua is also a “Distinguished Researcher” of the University of the Basque Country (UPV/EHU) and director of BasQ, the initiative to develop Quantum Technologies in the Basque Country. 

Javier Aizpurua achieved his Ph.D. at the University of the Basque Country on the theory of plasmons excitation by fast electron beams. After research positions at Chalmers University of Technology (Sweden) and at the National Institute of Standards and Technology -NIST- (USA), he joined DIPC as a Research Fellow. Since 2008, Aizpurua has been leading his group of Nanophotonics at the Center of Materials Physics at the Spanish Council for Scientific Research, and since 2024, he has joined Ikerbasque as a Research Professor. 

Aizpurua studies the interaction between light and matter at the nanoscale, with special emphasis on the optical response of metallic nanoantennas and quantum effects in plasmonics. He has introduced novel theoretical models and calculations which have helped to understand light-matter interactions in a variety of spectroscopy and microscopy techniques highly relevant to nanophotonics. The study of quantum effects in the optical response of all of these situations has guided his scientific career, taking him to a leading international role in the research of Quantum Nanooptics, with seminal contributions in the field.