title: Charge-induced nematicity in FeSe.
abstract: The spontaneous appearance of nematicity, a state of matter that breaks rotation but not translation symmetry, is one of the most intriguing properties of the iron-based superconductors (Fe SC), and has relevance for the cuprates as well. Establishing the critical electronic modes behind nematicity remains a challenge, however, because their associated susceptibilities are not easily accessible by conventional probes. Here, using FeSe as a model system, and symmetry-resolved electronic Raman scattering as a probe, we unravel the presence of critical charge nematic fluctuations near the structural/nematic transition temperature, [Formula: see text] 90 K. The diverging behavior of the associated nematic susceptibility foretells the presence of a Pomeranchuk instability of the Fermi surface with d-wave symmetry. The excellent scaling between the observed nematic susceptibility and elastic modulus data demonstrates that the structural distortion is driven by this d-wave Pomeranchuk transition. Our results make a strong case for charge-induced nematicity in FeSe.
authors.affiliation: Laboratoire Matériaux et Phénomènes Quantiques, CNRS UMR7162, Université Paris Diderot, Paris Cedex 13, France;
authors.forename: Pierre
authors.initials: P
authors.lastname: Massat
authors.affiliation: Laboratoire Matériaux et Phénomènes Quantiques, CNRS UMR7162, Université Paris Diderot, Paris Cedex 13, France;
authors.forename: Donato
authors.initials: D
authors.lastname: Farina
authors.affiliation: Laboratoire Matériaux et Phénomènes Quantiques, CNRS UMR7162, Université Paris Diderot, Paris Cedex 13, France;
authors.forename: Indranil
authors.initials: I
authors.lastname: Paul
authors.affiliation: Institut Néél, CNRS Unité Propre de Recherche 2940, 38042 Grenoble, France; Institut Néél, Université Grenoble Alpes, 38042 Grenoble, France;
authors.forename: Sandra
authors.initials: S
authors.lastname: Karlsson
authors.affiliation: Institut Néél, CNRS Unité Propre de Recherche 2940, 38042 Grenoble, France; Institut Néél, Université Grenoble Alpes, 38042 Grenoble, France;
authors.forename: Pierre
authors.initials: P
authors.lastname: Strobel
authors.affiliation: Institut Néél, CNRS Unité Propre de Recherche 2940, 38042 Grenoble, France; Institut Néél, Université Grenoble Alpes, 38042 Grenoble, France;
authors.forename: Pierre
authors.initials: P
authors.lastname: Toulemonde
authors.affiliation: Laboratoire Matériaux et Phénomènes Quantiques, CNRS UMR7162, Université Paris Diderot, Paris Cedex 13, France;
authors.forename: Marie-Aude
authors.initials: MA
authors.lastname: Méasson
authors.affiliation: Laboratoire Matériaux et Phénomènes Quantiques, CNRS UMR7162, Université Paris Diderot, Paris Cedex 13, France;
authors.forename: Maximilien
authors.initials: M
authors.lastname: Cazayous
authors.affiliation: Laboratoire Matériaux et Phénomènes Quantiques, CNRS UMR7162, Université Paris Diderot, Paris Cedex 13, France;
authors.forename: Alain
authors.initials: A
authors.lastname: Sacuto
authors.affiliation: Department of Physics, Kyoto University, Kyoto 606-8502, Japan;
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kasahara
authors.affiliation: Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba 277-8561, Japan.
authors.forename: Takasada
authors.initials: T
authors.lastname: Shibauchi
authors.affiliation: Department of Physics, Kyoto University, Kyoto 606-8502, Japan;
authors.forename: Yuji
authors.initials: Y
authors.lastname: Matsuda
authors.affiliation: Laboratoire Matériaux et Phénomènes Quantiques, CNRS UMR7162, Université Paris Diderot, Paris Cedex 13, France; yann.gallais@univ-paris-diderot.fr.
authors.forename: Yann
authors.initials: Y
authors.lastname: Gallais
keywords: Raman scattering; nematicity; superconductivity