Birth and annihilation of topological defects on the nematic–isotropic interface during droplet coalescence

Coalescence of biphasic droplets embedded in free standing smectic A films

“…ref. 72, 75 and 76). The only report of a homologue (7CB) of the material studied here claims a tilted alignment with about 52° tilt angle.…”

The structure of disintegrating defect clusters in smectic C freely suspended films

“…Fig. 5 shows the experimental observation again (a) and the simulated texture (b) for the experimentally determined ratio a/b E 1.83 and c determined from eqn (7), c/b E 0.6. Instead of the director field, we show a color presentation where the intensity of the red channel of the image was set proportional to 1 + sin y, the blue channel to 1 À sin y, the green channel to 0.4(1 + sin y).…”

“…We did not search for further geometrical solutions but we hypothesize that other special configurations may exist, particularly for larger S 0 , which also meet the requirements listed above. The outer defects were placed in positions (AEa/2,AEb/2) as in the experiment, and the two inner defects at (AEc/2,0) with c computed from eqn (7). The colors were chosen as a crude approximation to the optics under crossed polarizers and a diagonal phase plate (see text).…”

“…Topological defects play a significant role in a huge variety of physical systems, including for example anisotropic soft matter, [1][2][3][4][5][6][7][8][9] biological matter, [10][11][12][13][14] superfluidic liquids, [15][16][17] quantum systems, [18][19][20] or even cosmology. 21,22 The close resemblance of topological defects in biological systems and in active nematics has been emphasized.…”

“…(a) is the experimental texture. (b) was simulated to roughly represent the model texture.The outer defects were placed in positions (AEa/2,AEb/2) as in the experiment, and the two inner defects at (AEc/2,0) with c computed from eqn(7). The colors were chosen as a crude approximation to the optics under crossed polarizers and a diagonal phase plate (see text).…”