Figure 2.

(a) Schematic representation of the model. (b) Time evolution of the excited-state population per exciton type. (c) Simulated fwhm of the different exciton distributions. (d–g) Cross sections of the distributions. (d) The initial distribution of the singlets after laser excitation. (e) The singlets split into triplet states. (f) Nonlinear triplet–triplet annihilation results in a delayed singlet distribution that is significantly narrower than both the triplet distribution and the prompt singlet distribution. (g) Practically all prompt singlets have either decayed to the ground state or split into triplets, leading to a total singlet distribution that is narrower than the laser excitation spot.