Controlled Replication of Butterfly Wings for Achieving Tunable Photonic Properties

TLDR

The Morpho Peleides wing scale was fully replicated by depositing a uniform Al₂O₃ layer via low‑temperature ALD and then removing the template at high temperature to produce an inverted, polycrystalline Al₂O₃ shell with precisely controlled thickness. The alumina replicas preserved the butterfly’s photonic bandgap and violet/blue reflection peaks, shifted to longer wavelengths due to altered periodicity and refractive index, and functioned as waveguides and beam splitters, offering reproducible, low‑cost building blocks for photonic integrated circuits.

Abstract

The fine structure of the wing scale of a Morpho Peleides butterfly was examined carefully, and the entire configuration was completely replicated by a uniform Al2O3 coating through a low-temperature ALD process. An inverted structure was achieved by removing the butterfly wing template at high temperature, forming a polycrystalline Al2O3 shell structure with precisely controlled thickness. Other than the copy of the morphology of the structure, the optical property, such as the existence of PBG, was also inherited by the alumina replica. Reflection peaks at the violet/blue range were detected on both original wings and their replica, while a simple alumina coating shifted the reflection peak to longer wavelength because of the change of periodicity and refraction index. The alumina replicas also exhibited similar functional structures as waveguide and beam splitter, which may be used as the building blocks for photonic ICs with high reproducibility and lower fabrication cost compared to traditional lithography techniques.