Population hole-burning using a triplet reservoir: S₁ ← S₀ transition of zinc porphin in n-octane

Optical hole-burning has been observed in the S1 ← S0 absorption of zinc porphin in n-octane by selective depletion of the ground state population and storage in the mestastable triplet state. In this way the homogeneous linewidths of S1 ← S0 for molecules in A and B sites of n-octane were measured between 1.6 and 4.5 K. Thermally induced dephasing was observed for B-site molecules with an activation energy of 14 cm-, equal to the separation between the two electronic components of S1. © 1979.