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The photoinduced effects in Y/sub 1-x/Pr/sub x/Ba/sub 2/Cu/sub
3/O/sub 7-delta/ (x=0.3 and 0.4) thin films were investigated.
After Pr doping the oxygen is harder to remove by high
temperature annealing from our annealing experiments compared
with pure YBa/sub 2/Cu/sub 3/O/sub 7-delta/ films. According to
Schuller model, we infer that the energy barrier of moving
oxygen ions in Y/sub 0.7/Pr/sub 0.3/Ba/sub 2/Cu/sub 3/O/sub
7-delta/ is larger than that of YBa/sub 2/Cu/sub 3/O/sub
7-delta/. However, the resultof relaxation time measurements
just contradict with the inference above. Consequently, we
conclude that the Schuller model is probably not correct.We also
observed the lower oxygen concerntration of the sample, the
larger photoinduced effect in it. This is just opposite to the
Kudinov model and Schuller model which predicts that, the low
oxygen concentration, the weaker photoinduced effect. So we
conclude that both models are all incorrect.The illuminations
experiments were also performed in Y/sub 1-x/Pr/sub x/Ba/sub
2/Cu/sub 3/O/sub 7-delta/ (x=0.3 and 0.4) thin films with full
oxygen content. The overdoping behavior at low temperature was
observed by transport measurements. However, the resistivity
increasing at higher temperatures after illumination is not
understood at present.
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