Abstract
We numerically investigated the propagation characteristics of Ga:ZnO (GZO) thin films embedded in a ZnWO4 background in the epsilon near zero (ENZ) region. We found that, for GZO layer thickness ranging between 2 - 100 nm (∼ 1/600 - 1/12 of ENZ wavelength), such structure supports a novel non-radiating mode with its real part of effective index lower than surrounding refractive index or even less than 1. Such a mode has its dispersion curve lying to the left of the light line in the background region. However, the calculated electromagnetic fields display non-radiating nature contrary to the Berreman mode, because the transverse component of the wave vector is complex, ensuring a decaying field. Furthermore, while the considered structure supports confined and highly lossy TM modes in the ENZ region, no TE mode is supported. Subsequently, we studied the propagation characteristics of a multilayer structure constituting an array of GZO layers in the ZnWO4 matrix considering the modal field's excitation using the end-fire coupling. Such a multilayer structure is analyzed using high-precision rigorous coupled-wave analysis and shows strong polarization selective and resonant absorption/emission, the spectral location and bandwidth of which can be tuned by judiciously selecting the thickness of the GZO layer and other geometrical parameters.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
