Tunable Plasmonic Crystals Induced from a Two Dimensional Electron Gas

A two dimensional electron gas (2DEG) with periodic variation of its screening,$^{1}$ geometry,$^{2}$ or carrier density$^{3}$ provides an electromagnetic medium for the formation of a broadly tunable plasmonic crystal (PC). By using a periodic gate to control the 2DEG density in GaAs/AlGaAs heterostructures, we have induced terahertz (THz) PCs consisting of several bipartite crystal units cells. The PC band structure, Tamm states, and electromagnetically induced transparency phenomena are observed utilizing a gate-controlled defect adjacent to the PC to generate a plasmonic mixing photovoltage. These integrated PCs have potential applications in the areas of frequency selective THz detection, strong light-matter interaction, and planar metamaterials. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. The work at Sandia National Laboratories was supported by the DOE Office of Basic Energy Sciences. $^{1}$U. Mackens, et. al., Phys. Rev. Lett. \textbf{53}, 1485 (1984). $^{2}$V. M. Muravev, et. al., Phys. Rev. Lett. \textbf{101}, 216801 (2008). $^{3}$G. C. Dyer, et. al., Phys. Rev. Lett. \textbf{109}, 126803 (2012).