W. Park et al., ENERGY-TRANSFER PROCESSES AND PHOTOLUMINESCENCE PROPERTIES OF HOMOGENEOUSLY-DOPED AND DELTA-DOPED ZNS-MN, Journal of crystal growth, 185, 1998, pp. 1123-1127
An investigation is reported of the energy transfer processes in ZnS:M
n by photoluminescence spectroscopy. At temperatures >50 K, the lumine
scence decay of homogeneously doped ZnS : Mn was strongly non-exponent
ial due to non-radiative energy transfer processes. The concentration
dependence of the effective lifetime was found to change with temperat
ure. Analysis of the temperature dependence showed that the energy tra
nsfer between Mn ions was active only for Mn concentrations >2%, and t
hat the energy transfer between Mn ions was mediated by an electric di
pole-dipole interaction. The delta-doped ZnS : Mn showed a faster deca
y due to the enhanced overlap between 3d and s-p host states caused by
lattice strain. From the temperature dependence, the two-dimensional
confinement of energy transfer was observed for large spacings between
doping planes. When the doping planes were brought close together, th
e delta-doped samples behaved similarly to the homogeneously doped ZnS
:Mn, indicating that the energy transfer was no longer two-dimensional
ly confined. (C) 1998 Published by Elsevier Science B.V. All rights re
served.