偏極中性子を活用した磁性研究

摘要

The principles of polarized neutron scattering are introduced in this short paper and scattering experiments utilizing these characteristics and their applications in research on condensed matter magnetism are discussed. The experimental techniques used in polarizing devices especially those in polarizing monochromators, supermirror guides, and ~3He filters are explained. Experiments on polarized neutron scattering measuring polarization-dependent cross sections in a single direction given by a guide field, referred to as 1-dimensional or longitudinal polarization analysis after this, and more advanced 3- dimensional polarization analysis, i.e. neutron polarimetry experiments, are presented and discussed. Examples of polarized neutron investigations into ferromagnetic nano-particles, shortrange magnetic correlations in a spin liquid state, spin fluctuations in itinerant magnetic materials, and the complicated magnetic ground states of frustrated spin systems are presented to demonstrate the unique strength of this probe in magnetic materials research. The advent of modern neutron scattering facilities using both steady-state and pulsed-neutron source instruments to complement each other should intensify the utilization of polarized neutrons even more to enhance the advantages of these quantum beams in materials research.