Two-dimensional arrays of periodically driven qubits can host inherently dynamical topological phases with anomalous chiral edge dynamics. These chiral Floquet phases are formally characterized by a dynamical topological invariant, the chiral unitary index. Introducing a quantity called the chiral mutual information, we show that this invariant can be precisely interpreted in terms of a quantized chiral transfer of quantum information along the edge of the system, and devise a physical setup to measure it.
@article{arxiv.1804.02004,
title = {Tracking the quantized information transfer at the edge of a chiral Floquet phase},
author = {Blake R. Duschatko and Philipp T. Dumitrescu and Andrew C. Potter},
journal= {arXiv preprint arXiv:1804.02004},
year = {2018}
}