Excited‐state kinetics for Nd(thd)3 and Tb(thd)3 chelate vapors and prospects as fusion laser media

Fluorescence decays for the Nd3+ : 4F3/2→4I11/2 transition at 1.06 μm and the Tb3+ : 5D4→7F5 transition at 545 nm were studied, using the vapor‐phase carrier chelate 2,2,6,6‐tetramethyl‐3, 5‐heptanedione and pulsed‐laser excitation, as functions of (1) ground‐ and excited‐state molecular densities and (2) local temperature. In each case, inferred excited‐state densities 1016–1017 cm−3 were sustained for times greater than several hundred nanoseconds.