Giant Photoresponsivity of Midinfrared Hyperbolic Metamaterials in the Photon-Assisted-Tunneling Regime

Abstract

Conventional solar cells cannot collect energy from abundant midinfrared light, because there are no suitable semiconductors of the right band gap. Hyperbolic metamaterials (HMMs) are proposed to realize broadband, omnidirectional, sensitive diodes operating in this spectral region. The authors show how the slow-light modes supported by HMMs can trap incident radiation in metal-insulator-metal tunnel junctions, for ultrafast optical rectification and photon-to-electron energy conversion that is orders of magnitude more efficient than in conventional optical rectennas.