Chern insulators are an example of topological insulators, special phases of matter that are not characterised by a local order parameter but rather by a global integer topological invariant, the Chern number. In spite of this, the characteristic length scale (correlation length) of the system can be determined via a local density of the Chern number (the local Chern marker). In this work, we study quenches (transitions between phases that happen in finite time) between phases with different Chern numbers. Specifically, we are interested in how the correlation length changes during the quench and how its value after the quench depends on the quench's speed. Disorder is introduced into the system such that translational symmetry is broken only in one direction and conserved in the other. Furthermore, a formula for computing the local Chern marker in a position-momentum basis is derived. Numerical calculations are used to determine the critical exponents of the Qi-Wu-Zhang model and to show that the Kibble-Zurek mechanism applies to quenches between phases with different Chern numbers.
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