One of the hallmark features of active nematics is the formation of oppositely charged, point-like, topological half-integer defects that exhibit creation/annihilation dynamics. So far, such ±1/2 defects have been found only in dense and spatially uniform active systems, and it has been argued that they are absent in dilute, phase-separated active systems. In our study, we show that phase-separated active nematics can form condensed -1/2 defects of a new kind. In stark contrast to the well-studied homogeneous case, these new defects coincide with density peaks, lack a positively charged counterpart, condense nematic fluxes, and coexist with undulating dense bands from which they are formed by a new hierarchical condensation phenomenon.
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