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arXiv · 2004.00213

Experimental observation of a first order phase transition in a complex plasma mono-layer crystal

M. G. Hariprasad·P. Bandyopadhyay·Garima Arora·A. Sen
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Abstract

The formation and melting of a mono-layered charged dust particle crystal in a DC glow discharge Argon plasma is studied. The nature of the melting/formation process is established as a first order phase transition from the nature of the variations in the Coulomb coupling parameter, the dust temperature, the structural order parameter and from the existence of a hysteresis behavior. Our experimental results are distinctly different from existing theoretical predictions for 2D crystals based on the KTHNY mechanism or the Grain boundary induced melting and indicate a novel mechanism that is akin to a fluctuation induced first order phase transition that has not been observed before in complex plasmas.

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M. G. Hariprasad, P. Bandyopadhyay, Garima Arora, A. Sen. 2020-04-01. Experimental observation of a first order phase transition in a complex plasma mono-layer crystal. https://doi.org/10.1103/physreve.101.043209

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