Laser induced quasicrystalline order in charge stabilised colloidal systems

Chinmay Das; H. R. Krishnamurthy

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arXiv · cond-mat/9805003

Laser induced quasicrystalline order in charge stabilised colloidal systems

Chinmay Das·H. R. Krishnamurthy

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Abstract

We have studied the ordering of a two dimensional charge stabilised colloidal system in the presence of a stationary one dimensionally modulated laser field formed by the superposition of two modulations with wavevectors $q_0 τ$ and $q_0/τ$, where $q_0$ is the wavevector corresponding to the first peak of the direct correlation function of the unperturbed liquid, and $τ$ is the golden mean. In the framework of the Landau-Alexander-McTague theory we find that a decagonal quasicrystalline phase is stabler than the liquid or the triangular lattice in certain regions of the phase diagram. Our study also shows a reentrant melting phenomena for larger laser field strengths. We find that the transition from the modulated liquid to the quasicrystalline phase is continuous in contrast to a first order transition from the modulated liquid to the triangular crystalline phase.

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Chinmay Das, H. R. Krishnamurthy. 1998-05-01. Laser induced quasicrystalline order in charge stabilised colloidal systems. https://arxiv.org/abs/cond-mat/9805003

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