Thin film membranes confine infrared light

The thin-film membranes are said to confine infrared light far better than bulk crystals, which are the established technology for infrared light confinement.

“The thin-film membranes maintain the desired infrared frequency, but compress the wavelengths, allowing imaging devices to capture images with greater resolution,” said Yin Liu, co-corresponding author of a paper on the work in Nature Communications and an assistant professor of materials science and engineering at North Carolina State University.

“We’ve demonstrated that we can confine infrared light to 10 per cent of its wavelength while maintaining its frequency – meaning that the amount of time that it takes for a wavelength to cycle is the same, but the distance between the peaks of the wave is much closer together. Bulk crystal techniques confine infrared light to around 97 per cent of its wavelength.”

“This behaviour was previously only theorised, but we were able to demonstrate it experimentally for the first time through both the way we prepared the thin-film membranes and our novel use of synchrotron near-field spectroscopy,” said Ruijuan Xu, co-lead author of the paper and an assistant professor of materials science and engineering at NC State.