Numerical study of the meta-nanopyramid array as efficient solar energy absorber

Conventional dielectric moth eye structure is well known to be antireflective, but cannot work well in the whole solar spectrum. In addition, it cannot be used as a light absorber. However, in some cases, light absorbing and harvesting are important for energy conversion from light to heat or electricity. Here, we propose a metamaterial-based nanopyramid array which shows near 100% absorbing property in the entire solar spectrum (i.e. 0.2-2.5 mu m). In addition, the high absorption performance of meta-nanopyramid array retains very well at a wide receiving angle with polarization-independent. Thus, it can dramatically improve the efficiency of the solar light absorbing. The efficient light absorbing property can be explained in terms of the synergetic effects of slow light mode, surface plasmon polariton resonance and magnetic polariton resonance. (C) 2013 Optical Society of America