Superconductivity-induced spectral weight transfer due to quantum geometry

Junyeong Ahn; Naoto Nagaosa

doi:10.1103/physrevb.104.l100501

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arXiv · 2106.12724

Superconductivity-induced spectral weight transfer due to quantum geometry

Junyeong Ahn·Naoto Nagaosa

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Abstract

Optical spectral weight transfer associated with the onset of superconductivity at high energy scales compared with the superconducting gap has been observed in several systems such as high-$T_c$ cuprates. While there are still debates on the origin of this phenomenon, a consensus is that it is due to strong correlation effects beyond the BCS theory. Here we show that there is another route to a nonzero spectral weight transfer based on the quantum geometry of the conduction band in multiband systems. We discuss applying this idea to the cuprates and twisted multilayer graphene.

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Junyeong Ahn, Naoto Nagaosa. 2021-09-07. Superconductivity-induced spectral weight transfer due to quantum geometry. https://doi.org/10.1103/physrevb.104.l100501

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