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Symmetry breakdown in franckeite.pdf (778.09 kB)

Symmetry Breakdown in Franckeite: Spontaneous Strain, Rippling and Interlayer Moiré

submitted on 11.08.2019, 16:07 and posted on 13.08.2019, 12:47 by Riccardo Frisenda, Gabriel Sanchez-Santolino, Nikos Papadopoulos, Joanna Urban, Michal Baranowski, Alessandro Surrente, Duncan K. Maude, Mar Garcia-Hernandez, Herre S.J. van der Zant, Paulina Plochocka, Pablo San-Jose, Andres Castellanos-Gomez

Franckeite is a naturally occurring layered mineral with a structure composed of alternating stacks of SnS2-like and PbS-like layers. Although this superlattice is composed of a sequence of isotropic two-dimensional layers, it exhibits a spontaneous rippling that makes the material structurally anisotropic. We demonstrate that this rippling comes hand in hand with an inhomogeneous in-plane strain profile and anisotropic electrical, vibrational and optical properties. We argue that this symmetry breakdown results from a spatial modulation of the van der Waals interaction between layers due to the SnS2-like and PbS-like lattices incommensurability.


ERC-StG 2017, 755655

Grant Graphene Core 2, 785219

MINECO, FJCI-2017-32919, FJCI-2015-25427 and FIS2015-65706-P


Email Address of Submitting Author


Consejo Superior de Investigaciones Cientificas



ORCID For Submitting Author


Declaration of Conflict of Interest

No conflict of interest