In:
Advanced Materials, Wiley, Vol. 30, No. 13 ( 2018-03)
Kurzfassung:
2D van der Waals (vdW) layered polar crystals sustaining phonon polaritons (PhPs) have opened up new avenues for fundamental research and optoelectronic applications in the mid‐infrared to terahertz ranges. To date, 2D vdW crystals with PhPs are only experimentally demonstrated in hexagonal boron nitride (hBN) slabs. For optoelectronic and active photonic applications, semiconductors with tunable charges, finite conductivity, and moderate bandgaps are preferred. Here, PhPs are demonstrated with low loss and ultrahigh electromagnetic field confinements in semiconducting vdW α‐MoO 3 . The α‐MoO 3 supports strong hyperbolic PhPs in the mid‐infrared range, with a damping rate as low as 0.08. The electromagnetic confinements can reach ≈λ 0 /120, which can be tailored by altering the thicknesses of the α‐MoO 3 2D flakes. Furthermore, spatial control over the PhPs is achieved with a metal‐ion‐intercalation strategy. The results demonstrate α‐MoO 3 as a new platform for studying hyperbolic PhPs with tunability, which enable switchable mid‐infrared nanophotonic devices.
Materialart:
Online-Ressource
ISSN:
0935-9648
,
1521-4095
DOI:
10.1002/adma.201705318
Sprache:
Englisch
Verlag:
Wiley
Publikationsdatum:
2018
ZDB Id:
1474949-X
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