phase change material

Control of Au nanoantenna emission enhancement of magnetic dipolar emitters by means of VO2 phase change layers

Active, ultra-fast external control of the emission properties at the nanoscale is of great interest for chip-scale, tunable and efficient nanophotonics. Here we investigated the emission control of dipolar emitters coupled to a nanostructure made of an Au nanoantenna, and a thin vanadium dioxide (VO2) layer that changes from semiconductor to metallic state.

Correlation between in situ structural and optical characterization of the semiconductor-to-metal phase transition of VO2 thin films on sapphire

A detailed structural investigation of the semiconductor-to-metal transition (SMT) in vanadium dioxide thin films deposited on sapphire substrates by pulsed laser deposition was performed by in situ temperature-dependent X-ray diffraction (XRD) measurements. The structural results are correlated with those of infrared radiometry measurements in the SWIR (2.5-5 μm) and LWIR (8-10.6 μm) spectral ranges.

On the use of phase change materials applied on cork-coconut-cork panels: a thermophysical point of view concerning the beneficial effect in terms of insulation properties

This work explores the potentialities of combining a multi-layer eco-friendly panel with a phase change material coating. Although the work is based on a numerical approach performed by COMSOL Multiphysics® computer program, it can be considered as rigorous, robust, and optimized since the most important parameters added to the model were experimentally evaluated. The scientific soundness was guaranteed by a comparative analysis performed in two different times.

Adaptive tuning of infrared emission using VO2 thin films

Phase-transition materials provide exciting opportunities for controlling optical properties of photonic devices dynamically. Here, we systematically investigate the infrared emission from a thin film of vanadium dioxide (VO2). We experimentally demonstrate that such thin films are promising candidates to tune and control the thermal radiation of an underlying hot body with different emissivity features. In particular, we studied two different heat sources with completely different emissivity features, i.e. a black body-like and a mirror-like heated body.

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