遍歴電子反強磁性体Mn3Siについて

概要

論文の詳細を見る
Mn3Si is an itinerant electron antiferromagnet with an incommensurate spin structure of a wave vector Q of 0.425a*111 below the Neel temperature of 23K. By neutron diffraction studies 3rd harmonic satellites have been found to exist at low temperatures at the 3Q positions expected from the propagation wave vector Q of the fundamental satellite. The magnitude of the magnetic moments of the 3rd harmonics is about 1/40 that of the fundamental. The 3rd harmonic satellites did not follow the usual temperature variation of a magnetization curve but disappeared abruptly above 9K. Associated with this transition the intensity of the fundamental satellites changed slightly and the presence of the 3rd harmonics suppressed the amplitude of the fundamental SDW. This transition was confirmed by specific heat measurements showing a small hump at 8.5K, which persists to high magnetic fields of more than 6T. The existence of the 3rd harmonics satellites suggests that a transverse sinusoidal structure with spins modulating in the (110) or (210) plane is the most probable spin structure of Mn3Si.