The discussion focuses on interpreting dispersion curves for phonons, which represent allowed energy levels for various wavevectors in lattice vibrations. It is established that negative frequencies in these curves indicate lattice instability. Additionally, all phonons can be excited by neutrons, and while calculating phonon cross-sections can help identify observable phonons, the specifics of this calculation were not detailed. The conversation also highlights that dispersion curves exist for other excitations, such as electronic excitations measured by Angle-Resolved Photoemission Spectroscopy (ARPES) and spin waves measured by neutron scattering.
PREREQUISITESPhysicists, materials scientists, and researchers involved in solid-state physics, particularly those studying lattice dynamics and excitations in materials.
The quanta of lattice vibrations are the phonons, and the dispersion tells what allowed energies exist for various wavevectors. Also, if it happens that you have negative (imaginary) frequencies, then this tells you that you have a lattice instability.kimmylsm said:what can be interpret from dispersion curve of phonon?
kimmylsm said:how to find whether a phonon can loose all its energy to a neutron from dispersion curves?
kimmylsm said:are there dispersion curves for other atom apart from phonon?