This paper investigates the temperature-field scale invariance of non-Fermi liquid thermodynamic, transport, and Hall quantities in the non-superconducting iron-pnictide Ba(Fe1/3Co1/3Ni1/3)2As2. The researchers find evidence of quantum criticality at zero temperature and applied magnetic field, characterized by a linear-in-temperature resistivity and a scattering rate obeying a universal scaling relation between temperature and applied magnetic fields. The isotropic field response and lack of pressure sensitivity suggest a unique quantum critical system unaffected by pairing instability.

Yasuyuki Nakajima, Tristin Metz, Christopher Eckberg, Kevin Kirshenbaum, Alex Hughes, Renxiong Wang, Limin Wang, Shanta R. Saha, I-Lin Liu, Nicholas P. Butch, Daniel Campbell, Yun Suk Eo, David Graf, Zhonghao Liu, Sergey V. Borisenko, Peter Y. Zavalij, Johnpierre Paglione