Lattice-shifted nematic quantum critical point in FeSe1−xSx

Thumbnail Image
Date
2021-04-12
Authors
Chibani, S.
Farina, D.
Massat, P.
Cazayous, M.
Sacuto, A.
Urata, T.
Tanabe, Y.
Tanigaki, K.
Böhmer, Anna
Major Professor
Advisor
Committee Member
Journal Title
Journal ISSN
Volume Title
Publisher
Authors
Person
Canfield, Paul
Distinguished Professor
Research Projects
Organizational Units
Organizational Unit
Organizational Unit
Physics and Astronomy
Physics and astronomy are basic natural sciences which attempt to describe and provide an understanding of both our world and our universe. Physics serves as the underpinning of many different disciplines including the other natural sciences and technological areas.
Journal Issue
Is Version Of
Versions
Series
Department
Ames National LaboratoryPhysics and Astronomy
Abstract

We report the evolution of nematic fluctuations in FeSe1−xSx single crystals as a function of Sulfur content x across the nematic quantum critical point (QCP) xc ~ 0.17 via Raman scattering. The Raman spectra in the B1g nematic channel consist of two components, but only the low energy one displays clear fingerprints of critical behavior and is attributed to itinerant carriers. Curie–Weiss analysis of the associated nematic susceptibility indicates a substantial effect of nemato-elastic coupling, which shifts the location of the nematic QCP. We argue that this lattice-induced shift likely explains the absence of any enhancement of the superconducting transition temperature at the QCP. The presence of two components in the nematic fluctuations spectrum is attributed to the dual aspect of electronic degrees of freedom in Hund’s metals, with both itinerant carriers and local moments contributing to the nematic susceptibility.

Comments
Description
Keywords
Citation
DOI
Copyright
Collections