2026/07/20 by Eli Zoghlin, Matthew B. Stone, Vasile O. Garlea +3
#cond-mat.str-el #cond-mat.mtrl-sci
The phenomenon of frustration greatly enriches the accessible physics of quantum magnets. With this in mind we study the magnetism of NdCl3 using a combination of bulk properties measurements and neutron scattering techniques. The low-temperature heat capacity reveals two magnetic transitions at TN1 = 270 mK and TN2 = 180 mK. However, much of the magnetic entropy is released above TN1, manifesting as a broad peak centered at T* ≈ 450 mK. Single crystal elastic neutron scattering reveals highly anisotropic magnetic diffuse scattering above TN2, confirming that quasi-one-dimensional, short-range, antiferromagnetic order is the origin of the broad peak in the heat capacity. Magnetic Bragg peaks characterized by a k = (0 0 (1)/(2)) propagation vector emerge below TN1. Interestingly, the magnetic diffuse scattering persists for TN2 < T < TN1, indicating a regime of coexisting short and long-range order. The magnetic Bragg peaks exhibit an additional increase in intensity below TN2 with no change in k. Concomitantly, the diffuse scattering disappears indicating the attainment of full long-range order. While the precise nature of the ordered magnetic ground state remains unresolved, the observed magnetic scattering indicates predominate c-axis moments with a small ab-plane component. We propose that the quasi-one-dimensional behavior and the coexistence of short and long-range order are driven by frustration of anisotropic exchange interactions.