Temperature dependence of symmetric and asymmetric structured Au stripe waveguides

Abstract

The thermal effects on pigtailed 22-nm-thick, 5-mu m-wide and 1-cm-long Au stripe long-range surface plasmon polariton (LRSPP) waveguides, embedded in polymer/polymer layers and in polymer/silica layers, are theoretically and experimentally demonstrated. The polymer and silica cladding layers have thermo-optic coefficients of opposite signs. As the temperature varies the Au stripe LRSPP waveguide embedded in the polymer/polymer layers retains its symmetry in the refractive index, but that embedded in the polymer/silica layers becomes asymmetric in the refractive index. The thermal sensitivity in the optical output power of the symmetric structure is smaller than 0.02 dB/degrees C but the sensitivity of the asymmetric structure is similar to 0.3 dB/degrees C. These structures open up potential applications of the LRSPP waveguides for temperature independent/dependent photonic devices. (C) 2010 Elsevier B.V. All rights reserved.