Inelastic neutron scattering study quantum criticality of Ba(Fe1/3Co1/3Ni1/3)2As2

Exotic finite-temperature collective excitations beyond standard Landau Fermi liquid framework exhibit anomalous temperature dependences in the transport and thermodynamic properties in the vicinity of a quantum critical point i.e. the non-Fermi liquid behavior, which are often intimately linked to the appearance of unconventional cooper pairing in strongly correlated systems. Incompatible with previous observations, the quantum critical behavior in counter-doped non-superconducting Ba(Fe(1/3)Co(1/3)Ni(1/3))2As2 is not described by any known theoretical predictions. Using neutron scattering to study the highly unusual critical behavior in this material should enable us to further reveal the nature of the quantum critical points in iron pnictides, which might be a crucial step in understanding the pnictide physics in the future.