The design and realization of chip-scale plasmonic devices have been considerably facilitated by computational electromagnetic simulations and sophisticated nanofabrication techniques. For rapid device optimization, numerical simulations should be supplemented by simple analytical expressions capable of providing a reasonable estimate of the initial design parameters. In this paper, we develop an analytic approach and derive approximate expressions for the transmittance of metal-dielectric-metal (MDM) waveguides coupled to single, double, and periodic stub structures. Our method relies on the well-known analogy between MDM waveguides and microwave transmission lines, and enables us to use standard analytical tools in transmission-line theory. The advantage of our analytic approach over the previous studies is in accounting for the plasmon damping due to Ohmic losses and reflection-induced phase shift at the stub end. We found that the analyzed waveguide configurations can exhibit the characteristics of nanoscale filters and reflectors. We validate our analytical model by comparing its predictions with numerical simulations for several MDM waveguides with different stub configurations. The proposed theoretical results are particularly useful to reduce lengthy simulation times and will prove valuable in designing and optimizing MDM-waveguide-based photonic devices.

Date Published: 17 January 2011
PDF: 8 pages
Proc. SPIE 7941, Integrated Optics: Devices, Materials, and Technologies XV, 79411A (17 January 2011); doi: 10.1117/12.873651

Published in SPIE Proceedings Vol. 7941:
Integrated Optics: Devices, Materials, and Technologies XV
Jean Emmanuel Broquin; Gualtiero Nunzi Conti, Editor(s)