We make a detailed investigation on guided waves propagating in asymmetric indefinite medium waveguides. The dispersion relation of such guided modes is derived by using the normalized waveguide parameters. It is shown that the fundamental guided mode does not exist, the first-order guided modes can either exist in a restricted region or coexist with high-order modes, and the double degeneracy phenomenon does not always appear. A special dispersion curve associated with even surface modes is found, which leads to four surface modes coexisting. We demonstrate that both guided and surface modes can be greatly modulated by adjusting the parameters of the indefinite medium and its structure. We also analyze the normalized energy fluxes and confirm that the double degeneracy reflected from the fact of two different directions of energy flux, namely, coexistence of forward and backward waves.
© 2012 Optical Society of America
Original Manuscript: May 18, 2012
Revised Manuscript: June 11, 2012
Manuscript Accepted: July 7, 2012
Published: August 15, 2012
Xinglin Wang, Ming Shen, and An Jiang, "Modulation of guided and surface modes in asymmetric indefinite medium waveguides," J. Opt. Soc. Am. B 29, 2397-2402 (2012)