Van der Waals Phonon Polariton Microstructures for Configurable Infrared Electromagnetic Field Localizations. Issue 13 (1st May 2021)

• Record Type: Journal Article
• Authors: Huang, Wuchao; Sun, Fengsheng; Zheng, Zebo; Folland, Thomas G.; Chen, Xuexian; Liao, Huizhen; Xu, Ningsheng; Caldwell, Joshua D.; Chen, Huanjun; Deng, Shaozhi
• Is Part Of: Advanced science. Volume 8:Issue 13(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-05-01
• Subjects: electromagnetic field localizations -- microstructures -- nanoimaging -- phonon polaritons -- van der Waals crystals; Science -- Periodicals; 505
• DOI: 10.1002/advs.202004872
• Languages: English
• ISSNs: 2198-3844

Abstract

Abstract: Polar van der Waals (vdW) crystals that support phonon polaritons have recently attracted much attention because they can confine infrared and terahertz (THz) light to deeply subwavelength dimensions, allowing for the guiding and manipulation of light at the nanoscale. The practical applications of these crystals in devices rely strongly on deterministic engineering of their spatially localized electromagnetic field distributions, which has remained challenging. The polariton interference can be enhanced and tailored by patterning the vdW crystal α ‐MoO3 into microstructures that support highly in‐plane anisotropic phonon polaritons. The orientation of the polaritonic in‐plane isofrequency curve relative to the microstructure edges is a critical parameter governing the polariton interference, rendering the configuration of infrared electromagnetic field localizations by enabling the tuning of the microstructure size and shape and the excitation frequency. Thus, the study presents an effective rationale for engineering infrared light flow in planar photonic devices. Abstract : By taking advantage of the in‐plane hyperbolic phonon polariton and spatial confinement effects, the nanoscale tailoring of mid‐infrared electromagnetic field localizations in van der Waals α ‐MoO3 microstructures of different shapes and sizes is demonstrated. It is further shown that orientation of the in‐plane isofrequency curve relative to the microstructure edge is a critical parameter governing the localized electromagnetic field distributions.