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The growth of highly crystalline LaB6 films with an excellent optical response and low loss is reported, which will be useful for high‐performance photothermal device applications when combined with their inherent refractory properties. Optimum growth parameters for realizing uniaxial and coherent LaB6 thin films, exhibiting an excellent plasmonic response for near‐ to mid‐infrared device applications, are established. Numerical electromagnetic simulations of the epitaxial LaB6 nanostructures revealed that the electromagnetic field at the LaB6 surface can be as high as that of the Au nanostructures. Furthermore, the LaB6 nanostructures show resonance in the visible (red) to mid‐infrared region comparable to those of Au with the added advantage of improved temperature stability that can withstand harsh photothermal device operations.

Large-size composite carbon nanotubes/polyaniline as supercapacitor electrode material has been investigated for optimization of the areal specific capacitance. Polyaniline, as conductive polymer, is synthesized on the structure of carbon nanotubes by an in situ method. Thicker the composite electrode and higher polyaniline loading increase the gravimetric and volumetric specific capacitance. It is noticeable that this report's areal specific capacitance can reach approximately 6.5 F cm −2 .

We report the fabrication of a mid-infrared device using LaB6 – Al2O3 – LaB6 trilayers, with an array of LaB6 strips as the top layer. Uniaxially oriented lanthanum hexaboride (LaB6) films self-organized in a (100) orientation were adopted together with a lithographic process using laser direct writing followed by reactive ion etching. The fabricated infrared absorbers based on our electromagnetic design exhibited excellent resonant absorption and flexible tunability by changing the periodicity and width of the top LaB6 strips. We examined the performance of epitaxial and sputtered LaB6 films by fabricating two different types of absorbers using sputtered LaB6(100) and epitaxial LaB6(100) films for the bottom mirror layers. Owing to a difference in crystallinity, the latter exhibited a lower background in the absorption spectra as well as in the thermal emission spectra, indicating its good spectral selectivity.