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arXiv · 2606.16968

Electronic Green's function across the pseudogap to stripe transition in the $t$-$t'$-$J$ model

Martin Ulaga·Aritra Sinha·Alexander Wietek
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Abstract

Superconducting domes in strongly correlated electronic systems are often accompanied by charge density waves and peculiar features in the electronic structure. The appearance of a pseudogap, in particular, and its relation to charge density waves remains insufficiently understood. Here, we investigate the electronic Green's function of the underdoped $t$-$t'$-$J$ model of the cuprate superconductors using tensor network algorithms for finite temperature dynamics on cylinders of width $4$. We find the prominent momentum differentiation, the hallmark of the pseudogap, to be strongly dependent on $t'$, which develops into a momentum-dependent opening of a gap upon decreasing temperature, consistent with the formation of a Fermi arc at intermediate temperatures. The nodal gap around ${\bf k}=(\pi/2,\pi/2)$ closes and fills with increasing temperature as coherent stripe order melts into a regime of fluctuating charge clusters.

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Martin Ulaga, Aritra Sinha, Alexander Wietek. 2026-06-15. Electronic Green's function across the pseudogap to stripe transition in the $t$-$t'$-$J$ model. https://arxiv.org/abs/2606.16968

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