Thermally tunable mid-infrared nanocavity resonance of coupled surface plasmon-phonon polaritons

Authors

Satya R. Kachiraju, The University of Texas Rio Grande ValleyFollow
Zachary M. Brown
Sundar Kunwar
Long Chang
Imtiaz Ahmad, Texas Tech University
Pinku Roy
Vladimir Kuryatkov
Yejin Kwon
Ayrton A. Bernussi, Texas Tech University
Chase T. Ellis

Document Type

Article

Publication Date

7-28-2025

Abstract

Phase-change materials (PCMs) are essential for achieving tunability of metasurfaces. However, they frequently face limitations in the long-wave infrared range because of their lossy behavior. Here, we experimentally demonstrate a thermally tunable mid-infrared nanocavity resonance from coupled surface plasmon-phonon polaritons that are supported within a trilayer structure of metal-PCM layer-polar dielectric (Au-VO2-SiC). The top metal structures configure the Fabry-Perot cavity resonance near 840 cm−1 (11.9 µm), which is sensitively tunable and reversible with small changes in the VO2 refractive index ∆n near below its insulator-to-metal phase transition temperature where the loss is small. The maximum resonance shift of 7.7 cm−1 is induced by a small ∆n = 0.3 over a temperature change of 3°C. The tuning figure of merit is comparable to the current standard in photonic modulator applications.

Comments

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Recommended Citation

Kachiraju, Satya R., Zachary M. Brown, Sundar Kunwar, Long Chang, Imtiaz Ahmad, Pinku Roy, Vladimir Kuryatkov et al. "Thermally tunable mid-infrared nanocavity resonance of coupled surface plasmon-phonon polaritons." Optics Express 33, no. 15 (2025): 32051-32060. https://doi.org/10.1364/OE.555660

Publication Title

Optics Express

DOI

10.1364/OE.555660