Inhomogeneous broadening and gated hole burning in MgS : Eu and CaS : Eu in polymethylmethacralate (PMMA)

Previously, we have reported on high-density photon-gated spectral hole bur ning in europium-doped alkaline earth sulfides. Enhanced inhomogeneous broa dening of the zero phonon line (ZPL) has been achieved by embedding MgS : E u2 + and CaS : Eu2 + in PMMA and by compacting the sample by other means. W e investigate the inhomogeneous broadening as a function of the molecular w eight and the concentration of PMMA. Changes in both the line shapes and th e line widths of the ZPL were observed. With the enhanced broadening a much larger number of persistent power-gated holes have been burned in the ZPL. (C) 1999 Elsevier Science B.V. All rights reserved.