Quantum Criticality of the Quasi-One-Dimensional Heavy Fermion Material YbFe5P3

Eric D. Bauer¹, K. E. Avers^1,2, T. Asaba¹, S. Lee¹, S. Seo¹, Y. Liu¹, A. Weiland¹, S. M. Thomas¹, P. F.S. Rosa¹, R. Movshovich¹, J. D. Thompson¹, J. M. Lawrence¹, M. Continentino³, W. P. Halperin², F. Ronning¹

1. MPA-Q, Los Alamos National Laboratory, Los Alamos, NM, USA

2. Department of Physics and Astronomy, Northwestern University, IL, USA

3. Centro Brasileiro de Pesquisas Físicas, Department of Theoretical Physics, Rio de Janeiro, Brazil

Quantum criticality has been an organizing principle to explain the behavior of many families of quantum materials including the high-temperature cuprate and iron-based superconductors and f-electron heavy fermion compounds.  A central, unresolved issue is the role of quantum fluctuation dimensionality on the properties of the system.  Most work to date has focused on quantum criticality with two-dimensional (2-D) and three-dimensional (3-D) fluctuations.  Strong quantum fluctuations are expected in quasi-1-D materials and have recently been explored in 1-D f-electron materials such as CeRh₆Ge₄ [1], Yb₂Pt₂Pb [2], and YbAlO₃ [3].

YbFe₅P₃ crystallizes in the orthorhombic YCo₅P₃ structure type [4] with 1-D Yb chains along the b-axis with an Yb-Yb distance of 3.65 Å, while the inter-chain Yb-Yb spacing is 5.61 Å. Below about 5 K, the electrical resistivity reflects the presence of strong quantum fluctuations. Specific heat measurements show a similar strong enhancement at low temperatures reaching a constant value of C/T=1.5 J/mol K² below T = 0.5 K, indicating a heavy Fermi liquid state. No magnetic ordering is observed down to 80 mK. Chemical substation of Co or Ru for Fe drives YbFe₅P₃ to a quantum critical point. A magnetically ordered state is found for Co concentrations greater than 20%, beyond the quantum critical point.  In this talk, I will describe the physical properties of the quasi-1D heavy fermion material YbFe₅P₃ and the nature of quantum criticality in Yb(Fe_1-xM_x)₅P₃ (M=Co, Ru).

[1] B. Shen et al. Nature 579, 51 (2020); H. Kotegawa et al. JPSJ 88, 093702 (2019)

[2] L. S. Wu et al. Science 352, 1206 (2016)

[3] L. S. Wu et al. Nature Communications 10, 698 (2019)

[4] W. Jeitschko et al. J. Solid State Chem. 55, 331 (1984)