At room temperature photoconductivity measurements were performed for PbWO$_{4}$ crystals grown in varied technological conditions. In the near band-edge region three bands of photo-ionization absorption (310 nm, 330 nm and 338 nm) are detected. The intensity of these bands depends on a crystal perfection and quality. The value of a photocurrent under the excitation within the 330 nm band depends on preceding irradiation of a PbWO$_{4}$ crystal by the laser beam ($lambda _{ex}$ = 337 nm). The nature of defect centers related to the photo-ionization absorption bands is discussed.
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