Electrical Excitation of Surface Plasmon Polaritons Using an Au Ring Grating/GaAs Quantum Well Coupling Structure

In this paper, a compatible Au ring grating/GaAs quantum well (QW) coupling structure is used to electrically excite surface plasmon polaritons (SPPs). Once current injects into QW, SPPs are directly generated at the metal/semiconductor interface and coupled to a metal ring grating. The direct transmission of the light from QW are avoided by damaging QW coupling structure using ion-beam etching process, and only SPPs are coupled out. The scattering characteristics of generated SPPs demonstrate the capability of tunable electric field distribution, utilizing metal grating structures with different ring shape. The strong polarization-dependence characteristics of device are shown. The obvious application of well-designed electric excitation SPPs structures is proposed to be an approach to realize active plasmonic devices and integrated plasmonic circuits.