具有负折射率的三维光学超材料.
Jason Valentine1, Shuang Zhang, Thomas Zentgraf
1NSF Nano-scale Science and Engineering Center (NSEC), 3112 Etcheverry Hall, University of California, Berkeley, California 94720, USA.
Nature
|August 12, 2008
概括
研究人员开发了一种具有负折射率的3D光学元材料,克服了以前光学频率的限制. 这一突破使新的光学设备和现象成为可能,为先进的应用提供低损耗和广泛的光谱范围.
科学领域:
- *元材料和纳米光子学
- * 光学和光子学 * 光学和光子学
- * 材料科学 材料科学
背景情况:
- *元材料具有独特的特性,如负折射率,在自然界中不存在.
- *以前的负指数元材料 (NIM) 由于制造方面的挑战和高损耗,仅限于微波频率或光学频率的光学薄样品.
- * 实现大批量,低损耗的三维 (3D) 光学NIM一直是一个重大障碍.
研究的目的:
- * 设计一种3D光学元材料,在光学频率下具有负折射率.
- * 克服薄膜和2D元材料在批量光学应用中的局限性.
- * 为了证明实用光学设备的高价值 (低损耗).
主要方法:
- * 连锁"鱼网"结构的制造,以创建一个3D元材料.
- * 在广泛的光谱范围内对超材料的光学特性进行表征.
- *从超材料中构建一个镜,以实验证明负折射.
主要成果:
- * 3D光学元材料的实现,具有负折射率.
- * 获得了3.5的优点,这表明能量消耗很低.
- * 通过阴性相演变在镜配置中明确证明了负折射.
- * 在广泛的光谱范围内观察到负指数.
结论:
- *开发的3D光学超材料成功地在低损耗的光学频率上实现负折射率.
- * 这一突破使得功能性光学设备的创建成为可能,并为探索新的3D光学效果打开了道路.
- *潜在的应用包括超级镜头,光学道和高度定向的源.
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