Framework for Quasiperiodic Interfaces: Proximal Coincidence Point Set and Computation

TL;DR

This paper introduces a comprehensive theoretical and computational framework for analyzing quasiperiodic interfaces using proximal coincidence point set theory, extending classical models and revealing complex interfacial patterns and symmetries.

Contribution

It develops a unified approach combining cut-and-projection methods with spectral analysis to accurately model and explain quasiperiodic interface structures and symmetries.

Findings

Revealed generalized Fibonacci sequences in BCC tilt grain boundaries

Identified repetitive patterns in dislocation networks

Discovered emergence of 12- and 8-fold quasicrystals in high-angle BCC twist boundaries

Abstract

We present a unified theoretical and computational framework that bridges mathematical quasiperiodicity with classical crystallographic models. Based on a rigorous cut-and-projection construction, the proposed proximal coincidence point set (PCPS) theory extends the classical coincidence site lattice model and further incorporates physically motivated perturbations encoding interfacial atomic mobility as well as visual indistinguishability. Spectral characteristics of PCPS naturally motivate a conserved Landau-Brazovskii model combined with projection method, yielding unified high accuracy in resolving quasiperiodic order across the entire interfacial plane. Representative quasiperiodic features are revealed in our numerical results, including generalized Fibonacci sequences in BCC [110] tilt GBs, as well as repetitive patterns within the interstices of dislocation networks in low-angle BCC [100] twist GBs and phase boundaries between BCC and face-centered cubic crystals. In high-angle BCC [100] twist GBs, 12- and 8-fold quasicrystals emerge, while the PCPS theory combined with cyclotomic field projections further explains their restrictions of non-crystallographic symmetries. This framework not only provides a rigorous theoretical explanation for interface structures but also offers a path toward modeling other types of incommensurate structures.