Prof Romain Quidant (ICFO-Institut de Ciencies Fotoniques) – Metallic versus dielectric nanoresonators: Let’s get the best out of both

Home / News and Events / Lecture Series / Prof Romain Quidant (ICFO-Institut de Ciencies Fotoniques) – Metallic versus dielectric nanoresonators: Let’s get the best out of both


Dielectric nanophotonics with high-permittivity dielectric and semiconductor materials is becoming a relevant alternative to nanoplasmonics based on metallic nanoresonators. Eventually, both systems have pros and cons and, for a given experiment, the optimum nanophotonic design will depend on the specific properties to be met. In this talk, we present our recent advances in applied nanophotonics for reconfigurable metalenses, biosensing, additive manufacturing and disinfection. Depending on the application, we choose to work either with metal or dielectrics.

The first part of the talk focuses on our recent efforts towards reconfigurable metasurfaces. Our approach relies on dynamically controlling the refractive index in the close vicinity of a silicon metalens by means of a resistor embedded in a thermo-optical polymer. We demonstrate precise and continuous tuneability of the focal length, and achieve focal length variations larger than the Rayleigh length for voltage as low as 12V. The system time-response is of the order of 100ms, with the potential to be reduced with further integration. We also demonstrate that by solving the inverse problem, we are able to deterministically achieve any desired phase front. In the second part of the talk, we discuss the use of both dielectric and metallic nanoresonators in the context of biosensing and lab-on-a-chip technology. The sensors are integrated into a state-of-the-art PDMS microfluidic environment and their surface functionalized to achieve specific detection of the targeted biomarkers. We directly compare the performance of gold and silicon nanosensors and discuss their respective advantages. We also demonstrate multiplexed and quantitative detection of four protein cancer markers in human serum.

Finally, we discuss our latest advances in the field of thermoplasmonics, presenting two new application in additive
manufacturing (3D printing) and disinfection of surgical implants.


I received a PhD in Physics (2002) from the University of Dijon, in France. Right after defending my thesis, I joined ICFO as a postdoctoral researcher. This was the year of its creation and I was lucky enough to get actively involved into the early developments of the Institute. In 2006, I was appointed junior Professor (tenure-track) and group leader of the Plasmon NanoOptics group at ICFO. In 2009, I became tenure Professor both at ICFO and ICREA. While my core expertise is in fundamental nano-optics, I am very much interested in multidisciplinary research, interfacing physics with other disciplines of science, as well as in technology transfer.

Our research focuses on nano-optics, at the interface between Photonics (the science of light) and Nanotechnology. We use the unique optical properties of nanostructures as an enabling toolbox to design solutions to scientific and technological challenges, in a wide set of disciplines, from fundamental physics to biotechnology and medicine. This makes our group highly multidisciplinary and involved in both basic and applied research. The most fundamental part of our work is mainly directed towards enhanced light/matter interaction and quantum physics. From a more applied viewpoint, our team investigates news strategies to control light and heat at the nanometer scale for biomedical applications, including lab-on-a-chip technology and targeted hyperthermia. We are also extensively involved in tech-transfer, with three technologies being incubated in the ICFO KTT Launch pad.