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arXiv · 0805.1957

Change of Antiferromagnetic Structure near a Quantum Critical Point in CeRh1-xCoxIn5

M. Yokoyama·N. Oyama·H. Amitsuka·S. Oinuma·I. Kawasaki·K. Tenya·M. Matsuura·K. Hirota·T. J. Sato
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Abstract

The elastic neutron scattering experiments were carried out on the solid solutions CeRh_{1-x}Co_xIn_5 to clarify the nature of the antiferromagnetic (AF) state in the vicinity of the quantum critical point (QCP): x_c ~0.8. The incommensurate AF order with the wave vector of q_h=(1/2,1/2,~0.3) observed in pure CeRhIn_5 is weakly suppressed upon doping with Co, and a commensurate q_c=(1/2,1/2,1/2) and an incommensurate q_1=(1/2,1/2,~0.42) AF structures evolve at intermediate Co concentrations. These AF orders are enhanced at x=0.7, and furthermore the q_h AF order vanishes. These results suggest that the AF correlations with the q_c and q_1 modulations are significantly enhanced in the intermediate x range, and may be connected with the evolution of the superconductivity observed above x~0.3.

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M. Yokoyama, N. Oyama, H. Amitsuka, S. Oinuma, I. Kawasaki, K. Tenya, M. Matsuura, K. Hirota, T. J. Sato. 2008-05-14. Change of Antiferromagnetic Structure near a Quantum Critical Point in CeRh1-xCoxIn5. https://doi.org/10.1103/physrevb.77.224501

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