TY - JOUR
T1 - Direct observation of spin-flip excitations in MnSi
AU - Semadeni, F.
AU - Böni, P.
AU - Endoh, Y.
AU - Roessli, B.
AU - Shirane, G.
N1 - Funding Information:
Work at Brookhaven National Laboratory is supported by the division of Material Sciences, US DOE, under contract no. DE-AC02-76CH00016.
PY - 1999/6
Y1 - 1999/6
N2 - Using inelastic neutron scattering with polarization analysis, the magnetic excitations in the field induced ferromagnetic state of MnSi have been measured. The spin-flip cross-section displays well defined spin waves with Eq = Dq2+Δ at low-energy transfers. Above E≈3 meV, the excitations broaden significantly and their intensity becomes small. In addition, the slope of the dispersion curve becomes very steep indicating the transition from coherent magnetic excitations to single-particle excitations. The polarized beam experiments prove directly that the Stoner excitations are spin-flip. The non spin-flip excitations are only well defined at low E, whereas at higher E they are barely visible. They have a similar q-dependence as the parallel fluctuations δS∥M in other ferromagnets like Ni or EuS.
AB - Using inelastic neutron scattering with polarization analysis, the magnetic excitations in the field induced ferromagnetic state of MnSi have been measured. The spin-flip cross-section displays well defined spin waves with Eq = Dq2+Δ at low-energy transfers. Above E≈3 meV, the excitations broaden significantly and their intensity becomes small. In addition, the slope of the dispersion curve becomes very steep indicating the transition from coherent magnetic excitations to single-particle excitations. The polarized beam experiments prove directly that the Stoner excitations are spin-flip. The non spin-flip excitations are only well defined at low E, whereas at higher E they are barely visible. They have a similar q-dependence as the parallel fluctuations δS∥M in other ferromagnets like Ni or EuS.
UR - https://www.scopus.com/pages/publications/0344286685
U2 - 10.1016/S0921-4526(99)00077-0
DO - 10.1016/S0921-4526(99)00077-0
M3 - Conference article
AN - SCOPUS:0344286685
SN - 0921-4526
VL - 267-268
SP - 248
EP - 251
JO - Physica B: Condensed Matter
JF - Physica B: Condensed Matter
T2 - Proceedings of the 1998 2nd International Workshop on Polarised Neutrons for Condensed Matter Investigations, PNCMI '98
Y2 - 21 September 1998 through 23 September 1998
ER -