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1、The Key Laboratory of Weak Light Nonlinear Photonics, Ministry of Education Annual ReportAnnual Report 2002009 9 南开大学弱光非线性光子学 教育部重点实验室 Annual ReportAnnual Report 2002009 9 The Key Laboratory of Weak Light Nonlinear Photonics, Ministry of Education 南开大学弱光非线性光子学 教育部重点实验室 乌克兰国家科学院物理所的 Andrey Iljin 研究员来
2、访并进行学术交流。 （2009.2.16-3.14） 德国 Osnabrck 大学的 Peter Hertel 教授访问我院。（2009.4.7） 人工晶体研究所副院长黄存新教授受聘为兼职教授。（2009.5.8） 牛津大学 Robert A. Taylor 教授来访。（2009.5.24-5.27） 乌兹别克斯坦 Mirzo Ulugbek 国立大学的 Uyugun Vakhidovich Valiev 教授进行学术交流 访问。（2009.5.20-7.20） 麻省理工学院 Keith A. Nelson 教授访问了我院。（2009.6.13-17） 法国 Thales Research (
3、b) and (d) Closed-aperture Z-scan. 图 6 菲涅尔波带片主焦点。(a) 双层波带片 （b）单层波带片 Fig. 6. Photoghraphs of the main focal point: (a) two-layer zone plates, (b) single-layer zone plates. The length of the bars in the photographs is 20 m. 2009 年弱光非线性光子学教育部重点实验室年报 13 何偏振角度都相等。这些结果，对亚波长小孔在近场成像等方面的应用具有一定价值，特别是其偏振特性， 可以
4、实现偏振选择器件或设计不受偏振影响的光学器件。 By setting some effective structures, a rod or two teeth in the holes, the near-field transmission of the holes can be extraordinarily enhanced. We attribute this enhancement to the localized surface plasmon excited by the rod and the teeth. The enhanced transmission of the r
5、od-hole and the tooth-hole exhibits very strong polarization dependence, which is determined by the property of the localized surface plasmon directly. Starting from a basic optical theory, we find a simple way to design some polarization independent structures, i.e. cross-hole and four-tooth-hole.
6、The spectra of these two holes for different polarization angles almost overlap together. These results may be useful for some polarization dependence and independence applications. (图 7 不同偏振角度下双孔(a)和四孔(b)透射光谱 Fig. 7 Transmission spectra of (a) the tooth-hole for different polarization angles and (b
7、) four-tooth-hole for = 0, 30, and 45 respectively. Annual Report 2009 14 光子学材料及先进制备技术光子学材料及先进制备技术/ Photonics Materials and Advanced Fabrication Techniques 负责人：孔勇发 本方向涉及功能光学晶体、 微晶玻璃陶瓷、光子学微结构、纳米光子学、低维功能材料等方面。本年度发表论文13篇，申请发明专利3项，获得授权专利4项，在研课题经费423.8万元。取得的代表性成果如下： In this field, we mainly focused on th
8、e functional optical crystals, micro-crystal glass ceramics, photonic microstructure, nano-photonics, and nano-particulate films. 13 papers were published in international academic journals, 3 patents applicanted, and 4 patents issued. The total researching founds are more than 4 millions. This year
9、, we obtained some important results, they are mainly shown as following: 铁锰双掺铌酸锂(LN:Fe,Mn)晶体被认为是实现非挥发全息存储的理想材料(Nature 393, 665 (1998)， 但是该材料的响应时间在分钟量级，显然不能满足实际需求。本年度我们设计生长了锆铁锰三掺铌酸锂晶体(LN:Zr,Fe,Mn)，锆的掺入消除了反位铌缺陷，从而大大提高了载流子的迁移速度。LN:Zr,Fe,Mn 晶体非挥发存储的响应时间缩短至 0.95s（波长 532nm，光强 400 mW/cm2） ，灵敏度达到 1.31 cm/J
10、。该研究结果表明锆铁锰三掺铌酸锂晶体一种理想的全息存储介质。 Iron and manganese doubly doped LiNbO3 (LN:Fe,Mn) has been suggested for non-volatile photorefractive recording (Nature 393, 665 (1998), however its response time is still in the order of minutes. Here we present results on LiNbO3 triply doped with zirconium, iron, and
11、 manganese (LN:Zr,Fe,Mn). The co-doping with Zr eliminates undesirable intrinsic traps, which strongly enhances the charge transition speed. The response time of LN:Zr,Fe,Mn for nonvolatile holographic storage shortens to only 0.95 s (wavelength 532 nm, intensity 400 mW/cm2), and the sensitivity rea
12、ches 1.31 cm/J. Thus it seems that we have found an excellent recording medium for practical holographic storage devices. 利用聚焦的 514.5 nm 激光，我们研究了掺镁、 掺锆及名义纯铌酸锂晶体的光致畴反转。实验中发现这些晶体的组分虽然不同，但光致畴反转电场的降低却大致相同， 约为3 kV/mm。同时，反转畴总是在晶体c 面的光照区成核， 但在晶体的+c 面却是光照区的边沿首先贯通。 实验中还发现施加反向电场，或者对晶体进行温度高达 600C 的热处理，光致反转畴均保持
13、稳定。 综合上述及前人的实验现象， 我们提出了光致畴反转的理论模型（如图 2）。 Light-induced domain reversal of Mg-doped, Zr-doped, and nominally pure LiNbO3 crystals were investigated with focused 514.5 nm laser beams. It was found the light-reduced values of electric field for domain reversal are almost the same, about 3 kV/mm. Invert
14、ed domains always first nucleate on the c surface within the illuminated region but appear at the edge of the spot on the +c surface. The light-induced inverted domains are hard to be reversed by application of a reverse electric field or by heating to temperatures as high as 600C. Fig. 1. Holograph
15、ic recording and fixing characteristics of LN:Zr,Fe,Mn. Recording time is 30 seconds, readout time is about 80 minutes. The inset shows the recording process (0 s to 30 s) 图 1. LN:Zr,Fe,Mn 晶体中双色全息存储的记录和读出曲线。记录时间 30 秒，读出时间约 80 分钟。内图为细化的记录过程（0至 30 秒） 。 2009 年弱光非线性光子学教育部重点实验室年报 15 According to these ex
16、perimental results, we present a qualitative model (as shown in Fig. 2) on the light-induced domain reversal process in LiNbO3. 利用光诱导极化反转技术， 在近化学计量比掺镁铌酸锂晶体中实现了高质量畴结构的周期极化反转（Fig. 3） 。对近化学计量比掺锆铌酸锂晶体的抗光损伤强度进行了研究，研究结果发现其在 1064nm（10ns）波长下可达到 2 J/cm2以上 （此时铌酸锂样品未出现“灰迹”现象，透射的倍频光斑未发生形变） 。同时，经实验测量表明，该晶体在可见光区域其抗光损伤强度达到 10 MW/cm2（532nm）以上。因此，近化学计量比掺锆铌酸锂晶体有可能成为优秀的准相位匹配材料。 We processed the high-quality domain structure on the near-stoichiometric Zirconium doped lithium niobate crystals w
