Design and analysis of superlens based on complex two-dimensiona...

We theoretically demonstrate the imaging properties of a complex two-dimensional (2D) face-centered square lattice photonic crystal (PC) made from germanium cylinders in air background. The finite-difference time-domain (FDTD) method is employed to calculate the band structure and simulate image construction. The band diagram of the complex structure is significantly compressed. Negative refraction occurs in the second energy band with negative phase velocity at a frequency of 0.228 (2\pi c/a),