Dynamical phase diagram of the two-triplet states of singlet fission in molecular crystals. The bound states comprise the region of parameter space where the Bethe Ansatz phase acquires an imaginary part.
The triplet-triplet entanglement is measured through the Slater rank.
Triplets born out of singlet fission are entangled even if biexciton interactions are sufficiently weak that triplet pairs are unbound. Triplet extraction leads to a loss of classical information and therefore the quantum system becomes less entropic.