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arXiv · 2311.08932

The Anatomy of a Topological Phase Transition in a 2D Chern Insulator

Arjo Dasgupta·Indra Dasgupta
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Abstract

The onset of the topological phase transition in a two-dimensional model for a Chern Insulator, namely the Qi-Wu-Zhang(QWZ) model, is illustrated, with particular emphasis on the appearance of chiral edge-modes. The edge-modes are studied by analysing the dynamics of the edge-states in an equivalent model for a one-dimensional charge pump, using a technique known as dimensional extension. A further real-space analysis allows us to explain the onset of the topological phase transition in terms of time-reversal symmetry breaking and to quantitatively study the localisation of the edge-modes.

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Arjo Dasgupta, Indra Dasgupta. 2023-11-15. The Anatomy of a Topological Phase Transition in a 2D Chern Insulator. https://arxiv.org/abs/2311.08932

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