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采用溶剂蒸发法生长出透明的带隙宽度为2.96 e V的γ-CuI晶体。在紫外光激发下,该晶体在410、430 nm处分别呈现有近带边发射峰,另在720 nm附近还出现一个与样品碘缺陷有关的宽发射带。经碘退火后,样品720 nm发射带被基本抑制,而在420 nm处出现了一个更强的近带边发射峰。使用扫描相机分别测量了γ-CuI晶体各发射峰(带)的衰减时间谱,其中近带边发射峰的发光衰减时间常数均在数十皮秒量级,表明γ-CuI晶体具有极快的时间响应特性;而720 nm发射带的发光衰减时间常数主要在数十纳秒量级。X射线激发下,γ-CuI晶体具有435 nm近带边发射峰和680 nm发射带,其近带边发射对X射线能量响应的测量结果表明,当EX<49.1 ke V时,γ-CuI晶体闪烁光快分量对X射线的探测效率相对较高。
A transparent γ-CuI crystal with a bandgap width of 2.96 eV was grown by solvent evaporation. Under ultraviolet excitation, the crystal exhibits near-band edge emission at 410 and 430 nm, respectively, and a broad emission band associated with sample iodine defect appears near 720 nm. After iodine annealing, the 720 nm emission band of the sample was basically inhibited, while a stronger near-band edge emission peak appeared at 420 nm. The decay time spectrum of each emission peak (band) of γ-CuI crystal was measured by using a scanning camera. The decay time constant of emission near the band edge was on the order of tens of picoseconds, indicating that the γ-CuI crystal has very fast Time response characteristics; and 720 nm emission band luminescence decay time constant mainly in the order of tens of nanoseconds. X-ray excitation, the γ-CuI crystal has a 435 nm near-band edge emission band and a 680 nm emission band, and the measurement results of the near-band edge emission to the X-ray energy show that when EX <49.1 keV, Flickering light fast component of the X-ray detection efficiency is relatively high.