Topological robustness of thermally disordered lattices: From average structures to ensemble electronic properties
The study investigated whether a single, time-averaged crystal structure accurately represents a crystal at finite temperature. It found that the average structure fails to capture crucial effects like spin splitting and band-gap renormalization seen in individual configurations. Instead, a small ensemble of structures, like those from Monte Carlo simulations, better reproduces both the mean and spread of the electronic gap. Topological robustness is thus determined by the distribution over many fluctuating configurations.