Yao Jie, Liu Zhaowei, Liu Yongmin, Wang Yuan, Sun Cheng, Bartal Guy, Stacy Angelica M, Zhang Xiang
National Science Foundation (NSF) Nanoscale Science and Engineering Center (NSEC), 5130 Etcheverry Hall, University of California, Berkeley, CA 94720-1740, USA.
Science. 2008 Aug 15;321(5891):930. doi: 10.1126/science.1157566.
Negative refraction in metamaterials has generated great excitement in the scientific community. Although negative refraction has been realized in microwave and infrared by using metamaterials and by using two-dimensional waveguide structures, creation of a bulk metamaterial showing negative refraction at visible frequency has not been successful, mainly because of the significant resonance losses and fabrication difficulties. We report bulk metamaterials made of nanowires that show such negative refraction for all incident angles in the visible region. Moreover, the negative refraction occurs far from any resonance, resulting in a low-loss and a broad-band propagation at visible frequencies. These remarkable properties can substantially affect applications such as imaging, three-dimensional light manipulation, and optical communication.
超材料中的负折射在科学界引起了极大的轰动。尽管通过使用超材料以及二维波导结构在微波和红外波段实现了负折射,但尚未成功制造出在可见光频率下呈现负折射的块状超材料,这主要是由于显著的共振损耗和制造困难。我们报道了由纳米线制成的块状超材料,其在可见光区域对所有入射角均呈现出这种负折射。此外,负折射发生在远离任何共振的情况下,从而在可见光频率下实现了低损耗和宽带传播。这些卓越的特性会对成像、三维光操控及光通信等应用产生重大影响。