In the quasi-one-dimensional cuprate PrBa2Cu4O8, the Pr cations order antiferromagnetically at 17 K in zero field. Through a combination of magnetic susceptibility, torque magnetometry, specific heat, and interchain transport measurements, the anisotropic temperature-magnetic-field phase diagram associated with this ordering has been mapped out. A low-temperature spin-flop transition in the Pr sublattice is found to occur at the same magnetic field strength and orientation as a dimensional crossover in the ground state of the metallic-CuO chains. This coincidence suggests that the spin reorientation is driven by a change in the anisotropic Rudermann-Kittel-Kasuya-Yosida interaction induced by a corresponding change in effective dimensionality of the conduction electrons.
Xu, X. F., Carrington, A., Coldea, A. I., Enayati-Rad, A., Narduzzo, A., Horii, S., & Hussey, N. E. (2010). Dimensionality-driven spin-flop transition in quasi-one-dimensional PrBa2Cu4O8. Physical Review B, 81(22), . https://doi.org/10.1103/PhysRevB.81.224435