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超分辨技术是一种无需用减小波长或增大数值孔径的方法减小记录点尺寸而能读出超过衍射极限信号从而有效增加存储密度的一种方法.超分辨可以通过调整光学系统或者调整光盘的结构来实现.在超分辨光盘中,超分辨是基于掩膜的光学性质随入射激光强度的非线性变化而实现的.在磁光盘中第一次引入超分辨技术后,超分辨技术的应用有了很大发展,在目前是提高光盘存储密度的有效方法,在各类光盘中都有良好的应用.近场超分辨技术的出现使相变光盘的超高密度记录和读出成为可能.文章综述了超分辨光盘的发展现状和发展方向. 相似文献
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GeSe2非晶半导体薄膜中光致结构及性能变化 总被引:2,自引:0,他引:2
运用X射线衍射分析、红外光谱分析、扫描电镜分析和透射光谱分析,研究了GeSe2非晶半导体薄膜经514.5nm波长的氩离子激光辐照后的结构及性能变化。实验结果表明,经热处理和激光辐照后,薄膜的光学吸收边均移向短波长处,这种移劝随着辐照激光强度和辐照时间的增加而增大,并且在退火薄膜中是可逆的,扫描电镜分析结果表明,薄膜在激光辐照后有微晶析出,这种微晶的析出量随着辐照激光强度的增强而增加。 相似文献
196.
Temperature—Induced Magnetization Reorientation in GdFeCo/TbFeCo Exchange—Coupled Double Layer Films
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GdFeCo/TbFeCo exchange-coupled double-layer (ECDL) films used /or centre aperture type magnetically in-duced super resolution were investigated through experiments and theoretical calculation. The ECDL films were prepared by the magnetron sputtering method. Polar Kerr effect measurements showed that magnetization reorientation occurred in the GdFeCo layer with the temperature rising, which was subsequently analysed by the micromagnetic calculation based on the mean-field theory and a continuum model. Theoretical analysis is in agreement well with the experimental results. 相似文献
197.
We prepare TeOx thin films by vacuum evaporation of TeO2 powder.It is found that the as-deposited TeOx films can represent a two-component system comprising crystalline tellurium particles dispersed in an amorphous TeO2 matrix.Results of the static recording test show that the TeOx films have good writing sensitivity for shortwavelength laser beam (514.5nm).Primary results of the dynamic recording test at 514.5 nm are also reported.The carrier-to-noise ratio of 30dB is obtained for the disc using a TeOx film as the recording medium.Atomic force microscopy is used to study the microstructure of recorded marks.Micro-area morphology images show that the marks are mechanically deformed,and depressions and bulges have been imaged in the recorded marks,resulting in the scattering of the reading laser beam.The analytical results of transmission electron microscopy show that there is not obvious difference between the phase states of the tellurium particles before and after laser irradiation.Recording mechanisms of the TeOx thin films are discussed based on the experimental results. 相似文献
198.
Crystallization is induced by pulsed laser irradiation of as-deposited amorphous Ge_2Sb_2Te_5 films. Changes of the irradiated areas have been analyzed with the reflectivity contrast. As laser fluences increasing, the reflectivity contrast increases from 0%-2% to 14%-16%, which indicates the structure of asdeposited films transforms from amorphous to crystalline phases. The process of crystallization driven by the movement and rearrangement of atoms is described. And also the influence of the pulse duration on the threshold of crystallization is discussed, the results show that a lower threshold of crystallization can be produced for as-deposited films irradiated by the laser with short pulse duration. However, by the laser with long pulse duration, crystallization can only be formed with a higher threshold. The crystallization of films by irradiation of laser pulses is studied by Raman spectra. 相似文献
199.
A novel symmetrical charge transfer fluorene-based compound 2,7-bis (4-methoxystyryl)-9, 9-bis (2-ethylhexyl)-9H-fluorene (abbreviated as BMOSF) was synthesized and its nonlinear absorption was investigated using two different laser systems: a 140-fs, 800-nm Ti:sapphire laser operating at 1-kHz repetition rate and a 38-ps, 1064-nm Nd:YAG pulsed laser operating at 10-Hz repetition rate, respectively. Unique nonlinear absorption properties in this new compound were observed that rise from multiphoton absorption. The nonlinear absorption coefficients were measured to be 6.02×10-3 cm/GW (due to two-photon absorption, exciting wavelength is 800 nm) and 3.6×10-20 cm3/W2 (due to three-photon absorption, exciting wavelength is 1064 nm). This new compound possesses strong fluorescence induced by two-photon absorption and obvious three-photon absorption optical limiting effects. 相似文献
200.
Different pattern structures are obtained on the AgInSbTe(AIST) phase change film as induced by laser beam.Atomic force microscopy(AFM) was used to observe and analyze the different pattern structures.The AFM photos clearly show the gradually changing process of pattern structures induced by different threshold effects,such as crystallization threshold,microbump threshold,melting threshold,and ablation threshold.The analysis indicates that the AIST material is very effective in the fabrication of pattern structures and can offer relevant guidance for application of the material in the future. 相似文献