Inelastic Neutron Scattering: Spin Waves and Stoner Excitations

Description

This lecture covers the principles of inelastic neutron scattering, focusing on spin waves and Stoner excitations in itinerant magnets. It explains how spin waves can be damped by spin-flip excitations, the concept of the Stoner continuum, and how neutron scattering can measure dispersion relations. The lecture also discusses the sudden broadening of dispersion when crossing the Stoner gap, indicating spin flip induced by spin waves. Additionally, it explores the energy transfer in inelastic scattering and the different behaviors of spin waves in commensurate and incommensurate magnetic structures.

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