Strong diamagentism in Cuprate

Strong diamagnetism signal in pseudogap state has been reported recently in toque magnetometry experiment. A boson-fermion model is established based on the anisotropy of the state in $\mathbf{k}$-space, i.e. cooperons on antinodes and holes on nodes, to study this phenomenon. An algorithm of continuous time diagrammatic determinant quantum monte carlo is developed to simulate this model. The renormalization of the cooperon's band gives arise to large diamagnetism in agreement with experiments.