Highly confined phonon polaritons in monolayers of oxide perovskites

Abstract

Two-dimensional (2D) materials are able to strongly confine light hybridized with collective excitations of atoms, enabling electric-field enhancements and novel spectroscopic applications. Recently, freestanding monolayers of oxide perovskites have been synthesized, which possess highly infrared-active phonon modes and a complex interplay of competing interactions. In this study, we evaluate central figures of merit for phonon polaritons in the tetragonal phases of the 2D perovskites SrTiO${}_3$, KTaO${}_3$, and LiNbO${}_3$, using density functional theory calculations. Specifically, we compute the 2D phonon-polariton dispersions, the propagation-quality, confinement, and deceleration factors, and we show that they are comparable to those found in the prototypical 2D dielectric hexagonal boron nitride. Our results suggest that monolayers of oxide perovskites are promising candidates for polaritonic platforms in the terahertz spectral range that enable possibilites to control complex phases of matter through strongly enhanced electromagnetic fields.

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Cited by in corpus (7)

• Cavity magnon-polaritons in cuprate parent compounds
• Observation of the Breakdown of Optical Phonon Splitting in a Two-dimensional Polar Monolayer
• Thermal and electrostatic tuning of surface phonon-polaritons in LaAlO3/SrTiO3 heterostructures
• Exact Ansatz of Fermion-Boson Systems for a Quantum Device
• Low-loss far-infrared surface phonon polaritons in suspended SrTiO3 nanomembranes
• Strongly confined Mid-infrared to Terahertz Phonon Polaritons in Ultra-thin SrTiO3
• Two-dimensional moiré phonon polaritons