Abstract
The unique properties of the emerging photonic materials, conducting nitrides and oxides, especially their tailorability, large damage thresholds, and, importantly, the so-called epsilon-near-zero (ENZ) behavior, have enabled novel photonic phenomena spanning optical circuitry, tunable metasurfaces, and nonlinear optical devices. This work explores direct control of the optical properties of polycrystalline titanium nitride (TiN) and aluminum-doped zinc oxide (AZO) by tailoring the film thickness, and their potential for ENZ-enhanced photonic applications. This study demonstrates that TiN–AZO bilayers support Ferrell–Berreman modes using the thickness-dependent ENZ resonances in the AZO films operating in the telecom wavelengths spanning from 1470 to 1750 nm. The bilayer stacks also act as strong light absorbers in the ultraviolet regime using the radiative ENZ modes and the Fabry–Perot modes in the constituent TiN films. The studied Berreman resonators exhibit optically induced reflectance modulation of 15% with picosecond response time. Together with the optical response tailorability of conducting oxides and nitrides, using the field enhancement near the tunable ENZ regime can enable a wide range of nonlinear optical phenomena, including all-optical switching, time refraction, and high-harmonic generation.
Original language | English (US) |
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Article number | 2109546 |
Journal | Advanced Materials |
Volume | 35 |
Issue number | 34 |
DOIs | |
State | Published - Aug 24 2023 |
Funding
S.S. and M.G.O. contributed equally to this work. The authors acknowledge support by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Award DE‐SC0017717 (TCO materials growth and characterization), the Office of Naval Research under Award N00014‐20‐1‐2199 (TCO optical characterization), and the Air Force Office of Scientific Research under Award FA9550‐20‐1‐0124 (transition metal nitrides studies). Use of the Center for Nanoscale Materials, an Office of Science user facility, was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE‐AC02‐06CH11357.
Keywords
- Berreman resonators
- aluminum-doped zinc oxide
- epsilon-near-zero materials
- metasurfaces
- tailorable absorbers
- titanium nitride
- transparent conducting oxides
ASJC Scopus subject areas
- Mechanics of Materials
- Mechanical Engineering
- General Materials Science