Fifteen years of very active research in the field plasmonics have enabled us to considerably advance light control on the nanometer scale. Beyond the original peak of inflated expectation, the assets of nanoplasmonics over other technologies became clearer, as well as its limitations. More recently, the field has entered into the “slope of enlightenment” in which the actual contribution of metallic nanostructures to future technologies has been better identified. In this talk, we will review different aspects of our research where metallic nanostructures are used as an enabling tool towards novel photonic functionalities, with special focus on biotechnologies.

1. On-a-chip biosensing with optical nanoresonators — Owing to the subwavelength confinement of plasmonic fields, the resonances of optical nano-antennas are extremely sensitive to tiny changes of their surroundings, as for instance induced by the binding of molecules at their surface. This makes them very good candidates for compact, sensitive and low cost biosensing. While last two decades have witnessed a diversity of nano-optical systems with outstanding sensitivity, their implementation into a real analytical device is only at its infancy. In this context, we present here our latest advances in the optical, label-free detection of biomarkers based on gold and silicon nanoantennas integrated into a state-of-the-art microfluidic platform [1-3].

2. Nanoscale heat control and its applications – Recent years have witnessed a growing interest in controlling temperature on the nanoscale motivated by applications to different fields, including information technology, chemistry and medicine. Under illumination at its plasmon resonance, a metal nanoparticle features enhanced light absorption, turning it into an ideal nano-source of heat, remotely controllable by light. Such a powerful and flexible photothermal scheme sets the basis of the emerging and fast-growing field of thermoplasmonics. In this second part of the talk we first briefly present the specificities of heat generation in metal nanoparticles. We then focus on the experimental methods that have been developed to further understand and engineer plasmonic-assisted heating processes on the nanoscale. Finally, we present a selection of applications, focusing on reconfigurable planar optics, 3D printing and biomedicine [5, 6].

References

[1] O. Yavas et al, ACS Sensors 3, 1376 (2018)
[2] O. Yavas et al, ACS Nano 13, 4582 (2019)
[3] J. Garcia et al, ACS Photonics 5, 3673 (2018)
[4] J. Garcia et al, in preparation (2019)
[5] A. Powell et al, Nano Lett. 18, 6660 (2018)
[6] De Miguel et al, Nano Lett. 19 2524 (2019)