Seminar Announcement: Simone Normani

Data pubblicazione: 02-mar-2022

Announcement

Wednesday, 16 March 2022, 15:00

Sala Grande Palazzina B via alla Cascata 56/C

"1-D Tamm Plasmon Devices: Towards the Colorimetric Detection of Bacteria"

Simone Normani

Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia,

Via Giovanni Pascoli, 70/3, 20133 Milano, Italy

E-mail: simone.normani@iit.it

Abstract

The possibility of detecting the presence of micrometer-sized analytes by contact or surface measurements without the restrains imposed by the need for appropriate microfluidic channels has been one of the great advantages of photonic crystals (PhC) as label-free passive probes. Coupling a silver layer to a one-dimensional PhC leads to the formation of a hybrid photonic-plasmonic state called a Tamm plasmon: since its electric field is mostly confined close to the outer surface of the device, the effects of the interaction with external factors on it are enhanced, potentially making shifts of the resonance peak a reliable spectroscopic readout for biochemical detection.

We report on the design and development of low-layer count 1-D photonic crystals coated with thin layers of silver for use as bacteria detectors, with the aim of obtaining colorimetric sensing. This kind of detectors could be of immediate use in contexts such as the health and safety field and the food processing and packaging industry, as they would provide easy-to-make and easy-to-use analog detectors to check the conditions of biological and alimentary items, such as meats, which are particularly sensible to the proliferation of E. coli colonies, as well as the direct environmental/biomedica l uses, for instance in water contamination assessment and the analysis of bodily fluid samples.