Experimental confirmation of long hyperbolic polariton lifetimes in monoisotopic (¹⁰B) hexagonal boron nitride at room temperature.

ABSTRACT: Hyperbolic phonon polaritons (HPhPs) enable strong confinements, low losses, and intrinsic beam steering capabilities determined by the refractive index anisotropy-providing opportunities from hyperlensing to flat optics and other applications. Here, two scanning-probe techniques, photothermal induced resonance (PTIR) and scattering-type scanning near-field optical microscopy (s-SNOM), are used to map infrared (6.4-7.4μm) HPhPs in large (up to 120×250μm2 near-monoisotopic >99%B10) hexagonal boron nitride (hBN) flakes. Wide (≈40μm) PTIR and s-SNOM scans on such large flakes avoid interference from polaritons launched from different asperities (edges, folds, surface defects, etc.) and together with Fourier analyses 0.05μm-1 resolution) enable precise measurements of HPhP lifetimes (up to ≈4.

SUBMITTER: Pavlidis G 

PROVIDER: S-EPMC10502608 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature