Manipulation of electron flow using near-zero index semiconductor metamaterials

We study the possibility of controlling the propagation of ballistic electrons using an electronic metamaterial with zero quantum index of refraction. This is obtained by tailoring the band structure of a semiconductor superlattice to exhibit a Dirac cone at the center of the Brillouin zone, creating an artificial quantum medium with zero refractive index for electrons. We demonstrate attractive functionalities, such as anomalous tunneling, ideal matching, electronic routing, cloaking, and focusing. We envision applications in nanoelectronics and sensing.