双负性媒质的频率范围已经接近可见光波段

美国研究人员最近制作的一种材料,在波长为813纳米的红外光波段,其导磁率和介电率都为负值。这是目前为止能实现双负性的材料所达到的最短波长,并且已经与可见光谱380-780纳米非常接近。之前的纪录为1500纳米。这个结果朝着实现可见光波段双负性材料(DN-NIMs)的目标前进了一大步。

Double-negative metamaterial edges towards the visible (Mar 16)

http://physicsweb.org/article/news/11/3/13 

Researchers in the US have created a metamaterial that has a negative magnetic permeability and negative electric permittivity for infrared light with a wavelength of 813 nm. This is claimed to be the shortest wavelength yet for such a metamaterial and lies just outside of the visible spectrum at 380-780 nm. The previous record had been about 1500 nm, and the result is an important step towards the creation of double-negative negative-index metamaterials (DN-NIMs) that operate in the visible range.