  We demonstrate the existence of unconventional rheological and memory
properties in systems of soft-deformable particles whose energy depends on
their shape, via numerical simulations. At large strains, these systems
experience an unconventional shear weakening transition characterized by an
increase in the mechanical energy and a drastic drop in shear stress, which
stems from the emergence of short-ranged tetratic order. In these weakened
states, the contact network evolves reversibly under strain reversal, keeping
memory of its initial state, while the microscopic dynamics is irreversible.
