Design of low-cost photonic crystal based three-dimensional invisibility cloak

In this paper, we investigated the design of a photonic-crystal based three-dimensional (3D) cloaking structure with low-cost and improved performance. The carpet cloaking structure with truly 3D geometry is designed at optical frequencies. Compared with microwave cloaks where materials with large anisotropy are needed, the designed 3D cloak can be constructed using isotropic dielectric materials with small material parameter variations, which makes it suitable for practical implementation. By applying two-layer phase mask based holographic lithography, the designed cloaking structures can be fabricated rapidly and at low-cost, which will pave the way towards the mass production of invisibility cloak.