An air waveguide of left-handed photonic crystal （PhC） formed by holographic lithography is proposed. The symmetry mismatch between the incident wave and the Bloch modes of the holographic PhC is used to guide light...An air waveguide of left-handed photonic crystal （PhC） formed by holographic lithography is proposed. The symmetry mismatch between the incident wave and the Bloch modes of the holographic PhC is used to guide light efficiently. By properly designing the waveguide, backscattering loss can be significantly reduced. Due to the unique advantages of holographic photonie crystals, the serious problems of material loss and fabrication difficulty in left-handed material waveguides are also avoided. Furthermore it is shown that high transmission efficiency is easily achieved in the frequencv region with effective refraction index near zero. These features may extend the possible guiding ability of holographic photonic crystal waveguide and its promising potential in the application of photonic integrated circuits.展开更多
The negative refraction and imaging effects in photonic crystals can be used to solve diffraction limit problem in near-field optics.Improving transmission efficiency and image resolution is a critical work for negati...The negative refraction and imaging effects in photonic crystals can be used to solve diffraction limit problem in near-field optics.Improving transmission efficiency and image resolution is a critical work for negative refraction imaging.We theoretically investigate the band structures,equi-frequency surfaces,electromagnetic wave propagation,and the image intensity distributions in a two-dimensional hexagonal photonic crystal consisting of hollow components.It is found that,in contrast to a hexagonal photonic crystal consisting of solid dielectric cylinders of the same radius,photonic crystals with hollow components can be used to optimize the all-angle negative refraction.Numerical simulations show that the transmission efficiency and resolution of image can be enhanced by changing the radii of the hollow air rods.展开更多
A method to extract phase shifts and reconstruct the object wave in generalized phase-shifting interferometry(GPSI)is proposed.The phase distribution of a standard phase object and the least-square method are used to ...A method to extract phase shifts and reconstruct the object wave in generalized phase-shifting interferometry(GPSI)is proposed.The phase distribution of a standard phase object and the least-square method are used to extract phase shifts over a wide range from 0 to𝜌π.Consequently,the tested object wave can be further reconstructed with the extracted phase shifts.It is accurate and applicable for GPSI of any frame number𝑂(N𝑂≥2).Computer simulation has verified its feasibility and validity.展开更多
基金Supported by the National Natural Science Foundation （60777008, 10804063 and 60907005）, the Shandong Natural Science Foundation （ZR2010AM025）, the Doctoral Research Foundation of Shandong Jianzhu University （XNBS0903）, and the Scientific Research Foundation for ROCS, SEM, China.
文摘An air waveguide of left-handed photonic crystal （PhC） formed by holographic lithography is proposed. The symmetry mismatch between the incident wave and the Bloch modes of the holographic PhC is used to guide light efficiently. By properly designing the waveguide, backscattering loss can be significantly reduced. Due to the unique advantages of holographic photonie crystals, the serious problems of material loss and fabrication difficulty in left-handed material waveguides are also avoided. Furthermore it is shown that high transmission efficiency is easily achieved in the frequencv region with effective refraction index near zero. These features may extend the possible guiding ability of holographic photonic crystal waveguide and its promising potential in the application of photonic integrated circuits.
基金the National Natural Science Foundation of China under Grant Nos 60907005,10804063 and 51102148the National Natural Science Foundation of Shandong Province under Grant Nos ZR2011FQ011 and ZR2010AM025+3 种基金the National Science and Technology Program of Shandong Province under Grant No 2011GGH20119the Research Award Fund for Outstanding Young Scientists of Shandong Province under Grant No BS2011DX023the Science&Technology Bureau of Shenzhen under Grant No 0014632063100426032the Independent Innovation Foundation of Shandong University under Grant No 2010TB019.
文摘The negative refraction and imaging effects in photonic crystals can be used to solve diffraction limit problem in near-field optics.Improving transmission efficiency and image resolution is a critical work for negative refraction imaging.We theoretically investigate the band structures,equi-frequency surfaces,electromagnetic wave propagation,and the image intensity distributions in a two-dimensional hexagonal photonic crystal consisting of hollow components.It is found that,in contrast to a hexagonal photonic crystal consisting of solid dielectric cylinders of the same radius,photonic crystals with hollow components can be used to optimize the all-angle negative refraction.Numerical simulations show that the transmission efficiency and resolution of image can be enhanced by changing the radii of the hollow air rods.
基金Supported by the National Natural Science Foundation of China under Grant No 61275014the Science and Technology Program of Shandong Province under Grant No 2011GGH20119the Natural Science Foundation of Shandong Province under Grant No ZR2011FQ011.
文摘A method to extract phase shifts and reconstruct the object wave in generalized phase-shifting interferometry(GPSI)is proposed.The phase distribution of a standard phase object and the least-square method are used to extract phase shifts over a wide range from 0 to𝜌π.Consequently,the tested object wave can be further reconstructed with the extracted phase shifts.It is accurate and applicable for GPSI of any frame number𝑂(N𝑂≥2).Computer simulation has verified its feasibility and validity.
