%0 Journal Article
%J Physical Review B
%D 2009
%T Lattice dynamics in magnetic superelastic Ni-Mn-In alloys: Neutron scattering and ultrasonic experiments
%A Moya, X.
%A Gonzalez-Alonso, D.
%A Manosa, L.
%A Planes, A.
%A Garlea, V. O.
%A Lograsso, T. A.
%A Schlagel, D. L.
%A Zarestky, J. L.
%A Aksoy, S.
%A Acet, M.
%K behavior
%K elastic-constants
%K ni2mnga
%K premartensitic phenomena
%K shape-memory alloys
%K transition
%M ISI:000267699200048
%P 214118
%R 10.1103/Physrevb.79.214118
%U ://000267699200048
%V 79
%X Neutron scattering and ultrasonic methods have been used to study the lattice dynamics of two single crystals of Ni-Mn-In Heusler alloys close to Ni50Mn34In16 magnetic superelastic composition. The paper reports on the experimental determination of the low-lying phonon-dispersion curves and the elastic constants for this alloy system. We found that the frequencies of the TA(2) branch are relatively low and it exhibits a small dip anomaly at a wave number xi(0) approximate to 1/3, which softens with decreasing temperature. Associated with the softening of this phonon, we also observed the softening of the shear elastic constant C' = (C-11-C-12)/2. Both temperature softenings are typical for bcc-based solids which undergo martensitic transformations and reflect the dynamical instability of the cubic lattice against shearing of {110} planes along < 1 (1) over bar0 > directions. Additionally, we measured low-lying phonon-dispersion branches and elastic constants in applied magnetic fields aimed to characterize the magnetoelastic coupling.
%Z 466XRTimes Cited:0Cited References Count:32
%8 06/01
%@ 1098-0121