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Local spin correlation orders emerge in a paramagnetic state, with notable examples such as the partial order, cooperative paramagnetism, and soliton spin liquid. The noncentrosymmetric intermetallic antiferromagnet Mn3RhSi also exhibits the local spin correlation order in the paramagnetic state as magnetic short-range order in a wide temperature range. Here, we show that the local spin correlation order has a spiral structure by neutron scattering measurement of a Mn3RhSi single crystal. The possible origins of the magnetic cluster formation are discussed in terms of the Lifshitz invariant and the Griffiths phase, and compared with the room-temperature skyrmion phase of Co7Zn7Mn6 and non-Fermi liquid behavior of β-Mn. Short-range magnetic orders emerge in a paramagnetic state, with notable examples such as the partial order, cooperative paramagnetism, and soliton spin liquid. Here, the authors use inelastic neutron scattering to investigate short-range magnetic order in Mn3RhSi single crystal finding evidence for a spin spiral cluster, which they suggest may be an origin of the anomalous physical property. [ABSTRACT FROM AUTHOR]

Starch retrogradation can be evaluated using X-ray diffraction (XRD) techniques, which can estimate the crystallinity of starch. It is well known that the crystallinity is reflected in the mechanical properties of foods and materials. Crystallinity should be also related to the structural dynamics of starch, but there are no reports on the relationship between these properties. In this study, we used quasi-elastic neutron scattering (QENS) to investigate changes in the molecular dynamics of cooked rice starch during retrogradation. The width of the measured QENS narrowed with retrogradation. The elastic incoherent structure factor (EISF) increased, which indicated that the molecular dynamics are spatially suppressed upon retrogradation. However, the width of the quasi-elastic scattering component was independent of retrogradation in the measured Q -range. Analysis of EISF with a bimodal continuous diffusion model, where low and high mobilities are assumed to correspond to crystalline and amorphous phases, respectively, showed that the fraction of the low-mobility component increases with retrogradation. The suppression of the molecular dynamics during retrogradation was correlated with the crystallinity evaluated by XRD. The molecular dynamics of the crystalline region that appeared after gelatinization and retrogradation were different from that of raw rice starch. These results suggest that molecular dynamics reflect the state of retrogradation and can be used to monitor retrogradation of starch in foods. [Display omitted] • A new method to evaluate the molecular dynamics of cooked rice was developed. • The molecular dynamics of cooked rice were spatially suppressed by retrogradation. • Raw starch and retrograded starch were structurally and dynamically different. • The correlation between starch crystallinity and molecular dynamics was evaluated. [ABSTRACT FROM AUTHOR]

We have investigated spin-wave excitations in a four-sublattice (4SL) magnetic ground state of a frustrated magnet CuFeO2, in which "electromagnon" (electric-field-active magnon) excitation has been discovered by recent terahertz time-domain spectroscopy [Seki et al., Phys. Rev. Lett. 105, 097207 (2010)]. In a previous study, we identified two spin-wave branches in the 4SL phase by means of inelastic neutron scattering measurements under applied uniaxial pressure [T. Nakajima et al., J. Phys. Soc. Jpn. 80, 014714 (2011)]. In the present study, we have performed high-energy-resolution inelastic neutron-scattering measurements in the 4SL phase, resolving fine structures of the lower-energy spin-wave branch near the zone center. Taking account of the spin-driven lattice distortions in the 4SL phase, we have developed a model Hamiltonian to describe the spin-wave excitations. The determined Hamiltonian parameters have successfully reproduced the spin-wave dispersion relations and intensity maps obtained in the inelastic neutron-scattering measurements. The results of the spin-wave analysis have also revealed physical pictures of the magnon and electromagnon modes in the 4SL phase, suggesting that collinear and noncollinear characters of the two spin-wave modes are the keys to understanding the dynamical coupling between the spins and electric dipole moments in this system. [ABSTRACT FROM AUTHOR]