TY - JOUR
T1 - Unconventional Charge Density Wave Order in the Pnictide Superconductor Ba(Ni1-xCox)(2)As-2
AU - Lee, Sangjun
AU - de la Pena, 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
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)], 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)], 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.
U2 - 10.1103/PhysRevLett.122.147601
DO - 10.1103/PhysRevLett.122.147601
M3 - Article
SN - 0031-9007
VL - 122
JO - Physical Review Letters
JF - Physical Review Letters
IS - 14
M1 - 147601
ER -