Background: A three-layered structure for solar cell model is designed. We consider a LHM
film bounded by a glass superstrate and silicon/or silicon nitride substrate.
Objective: The aim of this paper is to study transmittance, reflectance and absorptance in a three-layers
structure composed of a glass superstrate and LHM middle layer; and as a substrate, we will be using
silicon which is one of the widely used materials to enhance light absorption in multilayer structures. We
will also be alternating between silicon and silicon nitride substrates to show their influence on the optical
Method: Our analysis is based on the transfer matrix approach, which is a very powerful algorithm for
optical parameters calculation in multilayer structures. The transmittance, reflectance and absorptance are
formulated at some specific incidence angles, computed numerically as functions of the incident frequency
and finally plotted using MATLAB software.
Results: Numerical results provide an extremely high absorption for a specific left-handed material. Thus,
absorptance near 100% can be theoretically achieved within an ultra broad band if the negative index
layer is sandwiched in a specifically designed structure.
Conclusion: It is shown that the proposed structures lead to absorptance improvement over wide ranges
of frequency and incidence angles. It has been also noticed that the absorptance in a LHM between a glass
cover and a silicon substrate, is better than the absorptance in a LHM between a glass cover and a silicon
nitride substrate. With adjustable LHM layer thicknesses and for exact values of the refractive index, we
can achieve high values of the absorptance coefficient that can reach 100%. These proposed structures
can be designed and fabricated with existing and future nanotechnology to produce high efficiency solar