Nanoscale slot waveguides of hyperbolic metamaterials are proposed and demonstrated for achieving large optical field enhancement. The dependence of the enhanced electric field within the air slot on waveguide mode coupling and permittivity tensors of hyperbolic metamaterials is analyzed both numerically and analytically. Optical intensity in the metamaterial slot waveguide can be more than 25 times stronger than that in a conventional silicon slot waveguide, due to tight optical mode confinement enabled by the ultrahigh refractive indices supported in hyperbolic metamaterials. The electric field enhancement effects are also verified with the realistic metal-dielectric multilayer waveguide structure.
© 2012 Optical Society of America
Original Manuscript: April 26, 2012
Revised Manuscript: May 25, 2012
Manuscript Accepted: May 25, 2012
Published: July 12, 2012
Yingran He, Sailing He, and Xiaodong Yang, "Optical field enhancement in nanoscale slot waveguides of hyperbolic metamaterials," Opt. Lett. 37, 2907-2909 (2012)