Premium
Properties of Exciton States in NaI I. The Intrinsic Photoluminescence
Author(s) -
Fontana M. P.,
Blume H.,
van Sciver W. J.
Publication year - 1968
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.19680290117
Subject(s) - exciton , photoluminescence , excitation , luminescence , atomic physics , photoluminescence excitation , materials science , chemistry , molecular physics , condensed matter physics , physics , optoelectronics , quantum mechanics
The efficiency and the decay time of the intrinsic photoluminescence of NaI have been investigated as a function of temperature and uv excitation energy. Upon excitation in the band‐to‐band region, the efficiency and the decay time are constant at low temperatures and decrease above 77 and 60 °K, respectively. The decrease in the decay time is not correlated to radiationless transitions occurring within the luminescent center. Upon excitation in the exciton region, the luminescence efficiency reaches a maximum at 60 °K and decreases at both higher and lower temperatures. The high temperature behavior is similar to that produced by band‐to‐band excitation. At 5 °K the luminescence efficiency for exciton excitation is negligibly small. The low temperature behavior of the luminescence is explained in terms of localized exciton states and temperature activated transitions among them.