C-PHOM researchers at Purdue University have reported the first demonstration of a metal-free plasmonic metamaterial device in the near-infrared. Metals have many disadvantages such as high losses which make them poor choices for many plasmonic metamaterial devices in the optical range. The Purdue group replaced conventional metal with aluminum-doped zinc oxide, a semiconductor-based material that overcomes the drawbacks of metals. They demonstrated negative refraction in such a metamaterial and showed that its performance is about three orders higher than that of any metal-based designs. This demonstration could lead to real-world metamaterial devices and enable unraveling of many new physical phenomena. This work has been published in PNAS.