  Persistent homology (PH) was applied to probe the structural changes of
glasses under shear. PH associates each local atomistic structure in an
atomistic configuration to a geometric object, namely, a hole, and evaluates
the robustness of these holes against noise. We found that the microscopic
structures were qualitatively different before and after yielding. The
structures before yielding contained robust holes, the number of which
decreased after yielding. We also observed that the structures after yielding
approached those of quickly quenched glass. This work demonstrates the crucial
role of robust holes in yielding and provides an interpretation based on
geometry.
