Nowadays, economic development relies heavily on energy resources and energy technologies. Considerable efforts have been devoted to the design of novel materials for energy related applications, especially for the generation and storage of clean and renewable energies such as solar energy. Among these materials, wave functional materials such as metamaterials and photonic crystals are promising candidates due to their unusual properties. This course aims to provide students a detailed introduction and comprehensive understanding of wave functional materials. It will emphasize the underlying physical mechanism responsible for their unusual properties such as resonance enhancement of light absorption. Practical applications such as energy harvesting and storage, photon detection, and wireless power transfer will also be discussed. By the end of this course, students will gain essential knowledge and master necessary numerical and analytical techniques to design wave functional materials.