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Title: Low‐Loss Far‐Infrared Surface Phonon Polaritons in Suspended SrTiO 3 Nanomembranes
Phonon polaritons (PhPs), excitations arising from the coupling of light with lattice vibrations, enable light confinement and local field enhancement, which is essential for various photonic and thermal applications. To date, PhPs with high confinement and low loss are mainly observed in the mid‐infrared regime and mostly in manually exfoliated flakes of van der Waals (vdW) materials. In this work, the existence of low‐loss, thickness‐tunable phonon polaritons in the far‐infrared regime within transferable freestanding SrTiO3membranes synthesized through a scalable approach, achieving high figures of merit is demonstrated, which are comparable to the previous record values from the vdW materials. Leveraging atomic precision in thickness control, large dimensions, and compatibility with mature oxide electronics, functional oxide membranes present a promising large‐scale 2D platform alternative to vdW materials for on‐chip polaritonic technologies in the infrared regime.  more » « less
Award ID(s):
2340751 2442399
PAR ID:
10657241
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Advanced Functional Materials
ISSN:
1616-301X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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