Fig. 1.

Structure of the active turbulent flow in contact with an isotropic oil. a Confocal fluorescence micrograph (375 × 375 μm²) of the AN in the turbulent regime when in contact with an isotropic oil. An example of the proliferating +1/2 (blue) and −1/2 (red) defects is sketched on top of the image (Supplementary Movie 1). b Instantaneous flow field (vector plot) and computed Okubo–Weiss parameter field (density plot, arbitrary units), which is employed to determine the location and size of vortices. c Binary image corresponding to the Okubo–Weiss field. d Statistical analysis of the distribution of vortex sizes accumulated for a series of one thousand snapshots during the active turbulent flow. The solid line is an exponential fit to the data. The range of vortex sizes is limited by the field of view