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Melting of 2D Coulomb clusters in dusty plasmas

Ryuta Ichiki·Yuriy Ivanov·Matthias Wolter·Yoshinobu Kawai·Andre Melzer
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Abstract

The melting of 2D dust clusters caused by one additional particle in the lower layer has experimentally been observed to undergo a two-step transition, which divides the phase of the cluster into three stages. The first transition is a jump of the dust kinetic energy due to the onset of an instability of the lower-layer particle, shifting the cluster from an ordinary to a hot crystalline state. The second transition is the actual phase transition into a liquid state, which occurs at a decisively lower gas pressure. The detailed dynamical properties of the system during the transition were determined in terms of the normal mode analysis.

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Ryuta Ichiki, Yuriy Ivanov, Matthias Wolter, Yoshinobu Kawai, Andre Melzer. 2004-10-20. Melting of 2D Coulomb clusters in dusty plasmas. https://arxiv.org/abs/physics/0410172

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