Abstract
We report a nuclear magnetic resonance study of the Cu nuclei in the paramagnetic phase of Ca${}_{0.85}$Sr${}_{0.15}$CuO${}_{2}$. By measuring the temperature dependence of the magnetic and quadrupolar shift and of the spin-lattice relaxation rate, we have obtained the following major results. With decreasing temperature, Ca${}_{0.85}$Sr${}_{0.15}$CuO${}_{2}$ undergoes two successive crossovers: a dimensionality crossover from a two-dimensional to a three-dimensional (3D) Heisenberg antiferromagnet followed, very close to ${T}_{N},$ by a spin-degree crossover from a 3D Heisenberg to a 3D $\mathrm{XY}$ antiferromagnet. There is no evidence for any structural changes accompanying the magnetic phase transition. The values of the hyperfine coupling constants ${A}_{c},$ ${A}_{\mathrm{ab}},$ and $B$ have been determined.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
