  The letter resolves several intriguing and fundamental aspects of debonding
at soft interfaces, including the formation and persistence of regularly
arranged nanocavities and bridges, ``adhesion-debonding hysteresis'', and
vastly lower adhesive strengths compared to the absence of pattern formation.
The analysis shows the hysteresis to be caused by an energy barrier that
separates the metastable patterned configurations during withdrawal, and the
debonded state. The metastable morphological pathways involving cavitation and
peeling of contact zones engender substantially lower debonding forces.
