Optical response of an anisotropic superlattice as a negative phase velocity medium

Precise control of electromagnetic energy propagation is a fundamental requirement for next-generation energy-related photonic technologies. In this work, a non-magnetic anisotropic superlattice is investigated as an effective platform for realizing negative phase velocity and engineered energy transport at infrared frequencies. The structure consists of periodically repeated anisotropic thin films embedded between two isotropic dielectric environments with refractive indices n0 and n2. By appropriate tuning of the incident angle and geometric parameters, negative phase velocity propagation is achieved without magnetic activity, enabling unconventional control over electromagnetic energy flow. The optical response of the superlattice is analyzed using a transfer-matrix formalism combined with Bloch theory for p-polarized electromagnetic waves. The combined influence of layer thickness, incident angle, and operating frequency on reflectivity spectra and Bloch wave dispersion is systematically examined. The results identify tunable spectral regimes in which phase propagation is decoupled from energy transport, leading to left-handed behavior and highly controllable electromagnetic energy transmission. From an application-oriented perspective, the proposed anisotropic superlattice offers a versatile route toward compact photonic components for energy harvesting, infrared energy management, and electromagnetic energy routing. The ability to tailor energy flow through structural and angular tuning makes this platform attractive for integration into energy-efficient waveguides and advanced optical architectures for energy-processing technologies.