Negative refraction and imaging properties of the electromagnetic wave through a two-dimensional photonic crystal （PC） slab, which consists of a square lattice of elliptical dielectric rods immersed in the air backg...Negative refraction and imaging properties of the electromagnetic wave through a two-dimensional photonic crystal （PC） slab, which consists of a square lattice of elliptical dielectric rods immersed in the air background, is studied by the plane-wave expansion method and the finite-difference time-domain method. A point source placed in the vicinity of the PC slab can form a good-quality image spot through the PC slab for the incident frequencies within the second photonic band. The calculated result also shows that negative refraction occurs in this kind of PC slab.展开更多
We report the imaging properties of a two-dimensional rectangular-lattice photonic crystal （PC） slab consisting of rectangular metallic rods immersed in a dielectric background. By simulating the electromagnetic wav...We report the imaging properties of a two-dimensional rectangular-lattice photonic crystal （PC） slab consisting of rectangular metallic rods immersed in a dielectric background. By simulating the electromagnetic wave propagation through such a PC slab with the finite-difference time-domain method, we find that a point source placed in the vicinity of the PC slab can form a good-quality image through the slab. The frequency region where a good-quality image is formed can be controlled by choosing the direction along which the PC slab surface normal is placed.展开更多
This paper studies the focusing properties of a two-dimensional photonic crystal （PC） slab consisting of a triangular lattice of metallic cylinders immersed in a dielectric background. Through the analysis of the eq...This paper studies the focusing properties of a two-dimensional photonic crystal （PC） slab consisting of a triangular lattice of metallic cylinders immersed in a dielectric background. Through the analysis of the equifrequency-surface contours and the field patterns of a point source placed in the vicinity of the PC slab, it finds that both the image distance and image quality can be controlled by simply adjusting the refractive index of the background material.展开更多
A highly efficient W3 Y-branch filter in a two-dimensional photonic crystal slab with triangular lattice of air holes is designed and fabricated, and its transmission properties are measured. By accurately adjusting t...A highly efficient W3 Y-branch filter in a two-dimensional photonic crystal slab with triangular lattice of air holes is designed and fabricated, and its transmission properties are measured. By accurately adjusting the size of the resonant cavities, the minimum wavelength spacing of 7 nm between two channels is realized. The corresponding resonant wavelengths of the two cavities agree well with the calculated ones. This implies that this kind of fiIter may be promising in integrated wavelength division multiplexing system.展开更多
A novel reflected terahertz-emission microscopy is proposed and developed for improving the spatial resolution of THz imaging. When attaching a bow-tie antenna directly onto a thin generation crystal, the reflected TH...A novel reflected terahertz-emission microscopy is proposed and developed for improving the spatial resolution of THz imaging. When attaching a bow-tie antenna directly onto a thin generation crystal, the reflected THz waves can be collected and detected by a photoconductive antenna, and the spatial resolution is decided by the diameter of focused pump beam. In this way, the detected resolution can be largely improved and tunable. The configuration and characteristics of this microscopy are described in detail.展开更多
基金Supported by the National Key Basic Research Special Foundation of China under Grant No 2004CB719804, the National Natural Science Foundation of China under Grant Nos 10404036 and 10674185, and National Centre for Nanoscience and Technology of China under Grant No 2003CB7169, and the Supercomputing Centre, CNIC, CAS.
文摘Negative refraction and imaging properties of the electromagnetic wave through a two-dimensional photonic crystal （PC） slab, which consists of a square lattice of elliptical dielectric rods immersed in the air background, is studied by the plane-wave expansion method and the finite-difference time-domain method. A point source placed in the vicinity of the PC slab can form a good-quality image spot through the PC slab for the incident frequencies within the second photonic band. The calculated result also shows that negative refraction occurs in this kind of PC slab.
基金Supported by the National Basic Research Programme of China under Grant Nos 2004CB719804 and 2001CB610402, the National Natural Science Foundation of China under Grant Nos 10404036 and 10674185, the National Centre for Nanoscience and Technology in China under Grant No 2003CB7169, and the Supercomputing Centre, CNIC, Chinese Academy of Sciences.
文摘We report the imaging properties of a two-dimensional rectangular-lattice photonic crystal （PC） slab consisting of rectangular metallic rods immersed in a dielectric background. By simulating the electromagnetic wave propagation through such a PC slab with the finite-difference time-domain method, we find that a point source placed in the vicinity of the PC slab can form a good-quality image through the slab. The frequency region where a good-quality image is formed can be controlled by choosing the direction along which the PC slab surface normal is placed.
基金Project supported by the National Key Basic Research Special Foundation of China （Grant Nos 2004CB719804 and 2001CB610402）, the National Natural Science Foundation of China （Grant Nos 10404036 and 10674185）. The Support from the Supercomputing Center, CNIC, CAS is Also Acknowledged.
文摘This paper studies the focusing properties of a two-dimensional photonic crystal （PC） slab consisting of a triangular lattice of metallic cylinders immersed in a dielectric background. Through the analysis of the equifrequency-surface contours and the field patterns of a point source placed in the vicinity of the PC slab, it finds that both the image distance and image quality can be controlled by simply adjusting the refractive index of the background material.
基金Supported by the National Key Basic Research Programme of China under Grant No 2006CB921702, the National Natural Science Foundation of China under Grant Nos 10404036, 10525419, and 10634080, and the Supercomputing Center, CNIC, CAS.
文摘A highly efficient W3 Y-branch filter in a two-dimensional photonic crystal slab with triangular lattice of air holes is designed and fabricated, and its transmission properties are measured. By accurately adjusting the size of the resonant cavities, the minimum wavelength spacing of 7 nm between two channels is realized. The corresponding resonant wavelengths of the two cavities agree well with the calculated ones. This implies that this kind of fiIter may be promising in integrated wavelength division multiplexing system.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10390160 and 39890390. This work was performed at the Research Centre for Superconductor Photonics, 0saka University, Japan. We acknowledge Masato Suzuki for his technical assistance.
文摘A novel reflected terahertz-emission microscopy is proposed and developed for improving the spatial resolution of THz imaging. When attaching a bow-tie antenna directly onto a thin generation crystal, the reflected THz waves can be collected and detected by a photoconductive antenna, and the spatial resolution is decided by the diameter of focused pump beam. In this way, the detected resolution can be largely improved and tunable. The configuration and characteristics of this microscopy are described in detail.
