Van Hove tuning of AV3Sb5 kagome metals under pressure and strain

Armando Consiglio; Tilman Schwemmer; Xianxin Wu; Werner Hanke; Titus Neupert; Ronny Thomale; Giorgio Sangiovanni; Domenico Di Sante

doi:10.1103/physrevb.105.165146

arXiv · 2111.09342

Van Hove tuning of AV3Sb5 kagome metals under pressure and strain

Armando Consiglio·Tilman Schwemmer·Xianxin Wu·Werner Hanke·Titus Neupert·Ronny Thomale·Giorgio Sangiovanni·Domenico Di Sante

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Abstract

From first-principles calculations, we investigate the structural and electronic properties of the kagome metals AV3Sb5 (A = Cs, K, Rb) under isotropic and anisotropic pressure. Charge ordering patterns are found to be unanimously suppressed, while there is a significant rearrangement of p-type and m-type van Hove point energies with respect to the Fermi level. Already for moderate tensile strain along the V plane and compressive strain normal to the V layer, we find that a van Hove point can be shifted to the Fermi energy. Such a mechanism provides an invaluable tuning knob to alter the correlation profile in the kagome metal, and suggests itself for further experimental investigation. It might allow to reconcile possible multi-dome superconductivity in kagome metals not only from phonons, but also from the viewpoint of unconventional pairing.

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Armando Consiglio, Tilman Schwemmer, Xianxin Wu, Werner Hanke, Titus Neupert, Ronny Thomale, Giorgio Sangiovanni, Domenico Di Sante. 2021-11-17. Van Hove tuning of AV3Sb5 kagome metals under pressure and strain. https://doi.org/10.1103/physrevb.105.165146

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