Nanoscale Sensing Glass Transition of Nanoconfined Polymers Through Thermoplasmonic

Abstract

It is known that downsizing of polymers at the nanoscale causes their physical properties, such as glass formation temperature, to deviate from the corresponding bulk properties. This fact requires the control of such parameters, since today nanoscale polymers are part of the architecture of many devices and are becoming increasingly important in modern technologies. To register temperature parameters in nanosized materials, localized heat sources are required. These can be metal nanostructures that generate heat on a nanoscale under the action of light. Enhanced absorption under conditions of plasmon resonance makes it possible to induce heat at the nanoscale and, therefore, as a result, plasmonic nanostructures can act as nano-heaters. We propose an approach to create enhanced heating of plasmonic nanostructures by nanostructuring the substrate surface (thermostat), which is demonstrated on titanium/silicon nitride (TiN:Si) hybrid structures using Raman thermometry. Using this approach, we detect the local glass transition temperature in nanosized polymers (PMMA and PMMA-DR1) by heating it with a thermoplasmonic metasurface using Raman spectroscopy.