2014/03/20 by Lucile Savary, Eun-Gook Moon, Leon Balents · 8 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Antiferromagnetism #Critical phenomena #Critical point (mathematics) #Electronic and Structural Properties of Oxides #Quantum #Quantum critical point #Quantum phase transition #Quantum phases #Renormalization group #Strongly correlated material #Topological Materials and Phenomena #cond-mat.str-el
paper · pdf · doi:10.1103/physrevx.4.041027
published as Phys. Rev. X 4, 041027 (2014) · 5 pages + 8 pages of Supplementary Material, 3 figures + 1 supplementary figure
arxiv created 2014/03/20 · openalex publication_date 2014/11/13 · arxiv updated 2014/12/05 · openalex created_date 2019/06/27 · openalex updated_date 2026/08/06
Magnetic fluctuations and electrons couple in intriguing ways in the vicinity of zero-temperature phase transitions-quantum critical points-in conducting materials. Quantum criticality is implicated in non-Fermi liquid behavior of diverse materials and in the formation of unconventional superconductors. Here, we uncover an entirely new type of quantum critical point describing the onset of antiferromagnetism in a nodal semimetal engendered by the combination of strong spin-orbit coupling and electron correlations, and which is predicted to occur in the iridium oxide pyrochlores. We formulate and solve a field theory for this quantum critical point by renormalization group techniques and show that electrons and antiferromagnetic fluctuations are strongly coupled and that both these excitations are modified in an essential way. This quantum critical point has many novel features, including strong emergent spatial anisotropy, a vital role for Coulomb interactions, and highly unconventional critical exponents. Our theory motivates and informs experiments on pyrochlore iridates and constitutes a singular realistic example of a nontrivial quantum critical point with gapless fermions in three dimensions.