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arXiv · 1108.1975

Optical Tweezers as a Micromechanical Tool for Studying Defects in 2D Colloidal Crystals

Sungcheol Kim·Lichao Yu·Stephanie Huang·Alexandros Pertsinidis·Xinsheng Sean Ling
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Abstract

This paper reports on some new results from the analyses of the video microscopy data obtained in a prior experiment on two-dimensional (2D) colloidal crystals. It was reported previously that optical tweezers can be used to create mono- and di-vacancies in a 2D colloidal crystal. Here we report the results on the creation of a vacancy-interstitial pair, as well as tri-vacancies. It is found that the vacancy-interstitial pair can be long-lived, but they do annihilate each other. The behavior of tri-vacancies is most intriguing, as it fluctuates between a configuration of bound pairs of dislocations and that of a locally amorphous state. The relevance of this observation to the issue of the nature of 2D melting is discussed.

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Sungcheol Kim, Lichao Yu, Stephanie Huang, Alexandros Pertsinidis, Xinsheng Sean Ling. 2011-08-09. Optical Tweezers as a Micromechanical Tool for Studying Defects in 2D Colloidal Crystals. https://doi.org/10.1117/12.897416

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