Fig. 9
From: Schools of skyrmions with electrically tunable elastic interactions
Generation of skyrmions by relaxing electrohydrodynamic instabilities. a–c Polarizing micrographs (at different magnifications) of a dense skyrmion array created by relaxing the electrohydrodynamic instability. The scale bars are 100 µm. d Polarizing micrographs showing the as-prepared sample initially without skyrmions at no applied fields (left image), electrohydrodynamic instability at U = 7 V (2nd image from the left), skyrmions at low number density forming upon switching back to U = 0 and relaxing the sample from electrohydrodynamic instability (3rd image from the left), electrohydrodynamic instability in the same sample area upon again applying U = 10 V (4th image from the left), and, finally, skyrmions at high number density forming upon switching back to U = 0 again and allowing the instability to relax (5th image from the left). These images illustrate the control of the initial skyrmion packing fraction (by area, displayed in the top-right of the images), where the amplitude of U used to generate electrohydrodynamic instabilities corelates with the ensuing skyrmion number densities. White double arrows denote crossed polarizer orientations. Elapsed time, skyrmion packing fraction by area, applied voltage, and direction of E are marked in the corners of micrographs. The used electric field frequency was 10 Hz
