Rotational symmetry breaking at the incommensurate charge-density-wave transition in Ba(Ni, Co)2(As, P)2

• Verfasst von: Merz, Michael [VerfasserIn]
• Verfasst von: Wang, Liran [VerfasserIn]
• Verfasst von: Wolf, Thomas [VerfasserIn]
• Verfasst von: Nagel, Peter [VerfasserIn]
• Verfasst von: Meingast, Christoph [VerfasserIn]
• Verfasst von: Schuppler, Stefan [VerfasserIn]
• Titel: Rotational symmetry breaking at the incommensurate charge-density-wave transition in Ba(Ni, Co)2(As, P)2
• Titelzusatz: possible nematic phase induced by charge/orbital fluctuations
• Verf.angabe: Michael Merz, Liran Wang, Thomas Wolf, Peter Nagel, Christoph Meingast, and Stefan Schuppler
• E-Jahr: 2021
• Jahr: 16 November 2021
• Umfang: 16 S.
• Fussnoten: Gesehen am 12.01.2022 ; Im Titel ist die Zahl 2 tiefgestellt
• Titel Quelle: Enthalten in: Physical review
• Ort Quelle: Woodbury, NY : Inst., 2016
• Jahr Quelle: 2021
• Band/Heft Quelle: 104(2021), 18, Artikel-ID 184509, Seite 1-16
• ISSN Quelle: 2469-9969
• DOI: doi:10.1103/PhysRevB.104.184509
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1785750704

Abstract

Nematic phase transitions in high-temperature superconductors have a strong impact on the electronic properties of these systems. BaFe2As2, with an established nematic transition around 137 K induced by magnetic fluctuations, and BaNi2As2, a nonmagnetic analog of BaFe2As2 with a structural transition in the same temperature range, share a common tetragonal aristotype crystal structure with space-group type I4/mmm. In contrast to BaFe2As2 where collinear stripe magnetic order is found for the orthorhombic low-T phase, a unidirectional charge density wave together with (distorted) zigzag chains are observed for the triclinic low-T phase of BaNi2As2. Here we show that between the high- and low-T phases of Ba(Ni,Co)2(As,P)2 an additional phase with broken fourfold symmetry and dxz orbital order exists which is a promising candidate for charge/orbital-fluctuation-induced nematicity. Moreover, our data suggest that the enhanced Tc found for Ba(Ni,Co)2(As,P)2 for higher Co or P substitution levels might result from suppression of the (distorted) zigzag chains by reducing the contribution of the dxy orbitals.