K. Avinash

Observation of Naturally‐Occurring Waves in a Strongly Coupled Plasma

The Fourier spectra of longitudinal and transverse waves corresponding to random particle motion were measured in a two‐dimensional strongly coupled plasma. As a model of a strongly coupled plasma, a plasma crystal, i.e., lattice composed of negatively charged microspheres immersed in a plasma, is used. The phonons were found to obey a dispersion relation that assumes a Yukawa inter‐particle potential. The crystal was in a non‐thermal equilibrium, nevertheless phonon energies were almost equally distributed with respect to wavenumber over the entire first Brillouin zone.