TY - JOUR
T1 - Unconventional charge density wave order in the pnictide superconductor Ba(Ni1-xCox)2As2
AU - Lee, Sangjun
AU - De La Penã, Gilberto
AU - Sun, Stella X.L.
AU - Mitrano, Matteo
AU - Fang, Yizhi
AU - Jang, Hoyoung
AU - Lee, Jun Sik
AU - Eckberg, Chris
AU - Campbell, Daniel
AU - Collini, John
AU - Paglione, Johnpierre
AU - De Groot, F. M.F.
AU - Abbamonte, Peter
N1 - Funding Information:
This work was supported by U.S. Department of Energy, Office of Basic Energy Sciences Grant No. DE-FG02-06ER46285. Use of the SSRL was supported under DOE contract DE-AC02-76SF00515. Crystal growth was supported by Air Force Office of Scientific Research Grant No. FA9550-14-1-0332. P. A. and J. P. acknowledge support from the Gordon and Betty Moore Foundation’s EPiQS initiative through Grants No. GBMF4542 and No. GBMF4419, respectively. M. M. acknowledges a Feodor Lynen Fellowship from the Alexander von Humboldt Foundation.
Publisher Copyright:
© 2019 American Physical Society.
PY - 2019/4/12
Y1 - 2019/4/12
N2 - Ba(Ni1-xCox)2As2 is a structural homologue of the pnictide high temperature superconductor, Ba(Fe1-xCox)2As2, in which the Fe atoms are replaced by Ni. Superconductivity is highly suppressed in this system, reaching a maximum Tc=2.3 K, compared to 24 K in its iron-based cousin, and the origin of this Tc suppression is not known. Using X-ray scattering, we show that Ba(Ni1-xCox)2As2 exhibits a unidirectional charge density wave (CDW) at its triclinic phase transition. The CDW is incommensurate, exhibits a sizable lattice distortion, and is accompanied by the appearance of α Fermi surface pockets in photoemission [B. Zhou et al., Phys. Rev. B 83, 035110 (2011)PRBMDO1098-012110.1103/PhysRevB.83.035110], suggesting it forms by an unconventional mechanism. Co doping suppresses the CDW, paralleling the behavior of antiferromagnetism in iron-based superconductors. Our study demonstrates that pnictide superconductors can exhibit competing CDW order, which may be the origin of Tc suppression in this system.
AB - Ba(Ni1-xCox)2As2 is a structural homologue of the pnictide high temperature superconductor, Ba(Fe1-xCox)2As2, in which the Fe atoms are replaced by Ni. Superconductivity is highly suppressed in this system, reaching a maximum Tc=2.3 K, compared to 24 K in its iron-based cousin, and the origin of this Tc suppression is not known. Using X-ray scattering, we show that Ba(Ni1-xCox)2As2 exhibits a unidirectional charge density wave (CDW) at its triclinic phase transition. The CDW is incommensurate, exhibits a sizable lattice distortion, and is accompanied by the appearance of α Fermi surface pockets in photoemission [B. Zhou et al., Phys. Rev. B 83, 035110 (2011)PRBMDO1098-012110.1103/PhysRevB.83.035110], suggesting it forms by an unconventional mechanism. Co doping suppresses the CDW, paralleling the behavior of antiferromagnetism in iron-based superconductors. Our study demonstrates that pnictide superconductors can exhibit competing CDW order, which may be the origin of Tc suppression in this system.
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U2 - 10.1103/PhysRevLett.122.147601
DO - 10.1103/PhysRevLett.122.147601
M3 - Article
C2 - 31050473
AN - SCOPUS:85064393260
SN - 0031-9007
VL - 122
JO - Physical review letters
JF - Physical review letters
IS - 14
M1 - 147601
ER -