We show that colloidal crystals can be assembled by means of temperature gradients produced by lightabsorption (λ=1070 nm) in a 21 nm titanium thin film deposited on one of the cell´s walls. Depending on theposition of a 100x microscope objective focus within the 20 μm thick cell, three different regimes of crystalformation can be identified: 1) convective currents regime; 2) convective-thermophoresis regime, and 3)thermophoresis regime. We show that defects on the crystal can be modified dynamically by switching on andoff the laser beam. In addition, the crystal can be 2D manipulated along the substrate. This technique could leadto the formation of large area colloidal crystals for photonics applications.
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