Remarkably Robust and Correlated Coherence and Antiferromagnetism in (Ce₁₋ₓLaₓ)Cu₂Ge₂

Author

Halyna Hodovanets, Missouri University of Science and TechnologyFollow
S. L. Bud'Ko
W. E. Straszheim
V. Taufour
E. D. Mun
Hyunsoo Kim, Missouri University of Science and TechnologyFollow
R. Flint
P. C. Canfield

Abstract

We present magnetic susceptibility, resistivity, specific heat, and thermoelectric power measurements on (Ce_1-xLa_x)Cu₂Ge₂ single crystals (0 ≤ x ≤ 1). With La substitution, the antiferromagnetic temperature T_N is suppressed in an almost linear fashion and moves below 0.36 K, the base temperature of our measurements for x > 0.8. Surprisingly, in addition to robust antiferromagnetism, the system also shows low temperature coherent scattering below T_coh up to ∼0.9 of La, indicating a small percolation limit ∼9% of Ce. T_coh as a function of magnetic field was found to have different behavior for x < 0.9 and x > 0.9. Remarkably, (T_coh)² at H = 0 was found to be linearly proportional to T_N. The jump in the magnetic specific heat δC_m at T_N as a function of T_K/T_N for (Ce_1-xLa_x)Cu₂Ge₂ follows the theoretical prediction based on the molecular field calculation for the S = 1/2 resonant level model.

Recommended Citation

H. Hodovanets et al., "Remarkably Robust and Correlated Coherence and Antiferromagnetism in (Ce₁₋ₓLaₓ)Cu₂Ge₂," Physical Review Letters, vol. 114, no. 23, article no. 236601, American Physical Society (APS), Jun 2015.

The definitive version is available at https://doi.org/10.1103/PhysRevLett.114.236601

Department(s)

Physics

International Standard Serial Number (ISSN)

1079-7114; 0031-9007

Document Type

Article - Journal

Document Version

Final Version

File Type

text

Language(s)

English

Rights

© 2015 American Physical Society (APS), All rights reserved.

Publication Date

08 Jun 2015