Research On Electron Trapping Optical Storage Materials

Electron trapping optical storage material is a kind of recently developed material, which has important application in optical storage and IR upconversion. While this material was used on optical storage, it has some excellent properties , such as high storage density; rapid read-write speed, erase and repeat rewrite elc. While this material was used on IR up-conversion, it has many superior, for example, wide response range in IR, low threshold value and so on. In this paper, preparation and optically stimulated luminescence of the electron trapping optical storage material were studied .Rare earth elements doped CaS, SrS and CaSrS were prepared by carbon-powder atmosphere reducing method (CARM) and carbon-powder direct reducing method (CDRM) respectively.The superiority of two type methods was compared and the character of the material was researched.Results indicated that CDRM is obviously superior to CARM. CDRM is simple in processing and does not contaminated surrounding and device. The sample prepared with CDRM is thin and homogenous in size and it can be directly used without grinding. The optical property of these material synthesized with CDRM is also superior to that of CDRM.The structure and the propoerties of the material was studied with XRD, SEM, spectrometer and thermo-luminescence spectrometer. Results indicated that CaS, SrS, CaSrS materials doped with different rare earth elements are face-center cube. The lattice paremeter is 5.694A, 6.007 A|·, 5.853 A respectively. The excitation spectra of all samples have an excitation peak in ultra-violet and visible light. Luminescence spectra are mainly composed of three groups narrowband in all sample. Photo-stimulated luminescence(PSL) spectra is a broadband spectrum peaking at 635nm, 595 nm 和 619nm respectively. The decay of PSL is rapid, thermo-luminescence spectrum peak of CaS:Eu,Sm is at 420℃ and no peak was found with the samples of SrS:Eu, Sm and CaSrS: Eu, Sm in the range of instrument.The effects of calcinated temperature, calcinated time, rare earth types and content, aid-flux content and carbon powder content on the optical properties of sample were studied. A new standpoint of electron trapping optical storage principle was pointed out.