moire-metrology

Atomic relaxation, strain extraction, and multi-layer analysis for twisted 2D van der Waals heterostructures.

This is a Python re-implementation of the modeling tools developed for the papers listed under References. The goal is to make the methodology accessible as a pip-installable package, instead of a private collection of MATLAB scripts.

Features

  • Single-interface relaxation of twisted bilayer systems on a periodic triangular FEM mesh, with three solver options: damped Newton (analytic Hessian), implicit pseudo-time-stepping, and L-BFGS-B.

  • Multi-layer stack API (LayerStack) for heterostructures with any number of layers per flake, including fix_top / fix_bottom clamps.

  • Materials database with bundled GSFE parameterizations for graphene, hBN (AA, AA’), MoSe2/WSe2, and graphene/hBN heterointerfaces.

  • Strain extraction from measured moire patterns, implementing the closed-form inversion of Halbertal et al., ACS Nano (2022).

  • Constrained relaxation on a finite domain via PinningMap – pin known stacking configurations and relax the rest.

  • Plotting helpers for stacking-energy maps, elastic-energy maps, local twist angle, and displacement fields.

User Guide

API Reference

Project