2017/08/31 by Joel S. Helton, Susumu Jones, Susumu K. Jones +7 · 9 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Brillouin zone #Condensed matter physics #Ferromagnetism #Magnetic and transport properties of perovskites and related materials #Metastability #Multiferroics and related materials #Phase (matter) #Phase diagram #Physics #Quantum mechanics #Spin (aerodynamics) #Spin wave #Thermodynamics #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.96.104417
published in Physical review. B./Physical review. B 96(10) (American Physical Society) · v2: 8 pages, 7 figures v1: 7 pages, 7 figures
arxiv created 2017/09/12 · openalex publication_date 2017/09/13 · openalex created_date 2017/09/15 · arxiv updated 2017/09/18 · openalex updated_date 2026/08/05
While the spin dynamics of La0.7Ca0.3MnO3 in the ferromagnetic phase are known to be unconventional, previous measurements have yielded contradictory results regarding the damping of spin wave excitations. Neutron spectroscopy measurements on a sample with a transition temperature of Tc=257 K, higher than most single crystals, unambiguously reveal an anomalous increase in spin wave damping for excitations approaching the Brillouin zone boundary along the [100] direction that cannot be explained as an artifact due to a noninteracting phonon branch. Spin waves throughout the (HK0) plane display a common trend where the spin wave damping is dependent upon the excitation energy, increasing for energies above roughly 15 meV and reaching a full width at half maximum of at least 20 meV. The results are consistent with a model of intrinsic spatial inhomogeneity with phase separated regions approximately 18 \AA in size persisting over a large range of temperatures below Tc.