2025-03-13 カリフォルニア大学ロサンゼルス校 (UCLA)
Yilin Wong・A logarithmic spiral with a diameter of 500 μm, approximately half the diameter of a sewing needle.
＜関連情報＞
- https://newsroom.ucla.edu/releases/how-chemistry-and-force-etch-mysterious-spiral-patterns-on-solid-surfaces
- https://journals.aps.org/prmaterials/abstract/10.1103/PhysRevMaterials.9.035201
オイラー不安定性によって変調するGe/Cr/Au界面における金属支援化学エッチングパターン Metal-assisted chemical etching patterns at a Ge/Cr/Au interface modulated by the Euler instability
Yilin Wong and Giovanni Zocchi
Physical Review Materials Published: 3 March, 2025
DOI:https://doi.org/10.1103/PhysRevMaterials.9.035201
Abstract
We present a solid state system which spontaneously generates remarkable engraving patterns on the surface of Ge. The layered construction, with a metal film on the Ge surface, results in coupling of the metal catalyzed etching reaction with the long range stress field at the Ge-metal interface. The etching patterns generated have similarities with Turing patterns, hydrodynamic patterns, crack propagation, and biological form. We describe spirals, radial patterns, and more disordered structures. Euler buckling of the metal layer generates a characteristic wavelength for some patterns.
