The effects of photoinduced hole doping on YSrxBa2-xCu3Oy thin films a
re studied. Previously persistent photoinduced conductivity (PPC) and
T-c enhancement have been observed in YBa2Cu3Oy with y < 7. We show th
at these persistent photoinduced effects are absent in YSrxBa2-xCu3Oy
films with an oxygen content y < 7 if the oxygen deficiency is caused
by Sr doping, not by insufficient oxygenation. However, upon laser ill
umination, substantial increase of T-c and normal state conductivity a
re observed in YSrxBa2-xCu3Oy films annealed in reduced oxygen pressur
e. The conductivity decreases and relaxes back to its original value a
s the temperature approaches room temperature during the warm-up proce
ss. The relaxation of PPC is much faster than that observed in YBa2Cu3
Oy. We attribute these differences to the smaller lattice constants of
YSrxBa2-xCu3Oy.