We give the characteristic equation of a W-type fiber by solving Maxwell's equations along with boundary conditions at the interfaces. The cutoff condition of the fundamental mode is examined,and a novel W-type fi...We give the characteristic equation of a W-type fiber by solving Maxwell's equations along with boundary conditions at the interfaces. The cutoff condition of the fundamental mode is examined,and a novel W-type fiber working in S-band is designed.展开更多
The author gives a characterization of counterexamples to the Kodaira-Ramanujam vanishing theorem on smooth projective surfaces in positive characteristic.More precisely,it is reproved that if there is a counterexampl...The author gives a characterization of counterexamples to the Kodaira-Ramanujam vanishing theorem on smooth projective surfaces in positive characteristic.More precisely,it is reproved that if there is a counterexample to the Kodaira-Ramanujam vanishing theorem on a smooth projective surface X in positive characteristic,then X is either a quasi-elliptic surface of Kodaira dimension 1 or a surface of general type.Furthermore,it is proved that up to blow-ups,X admits a fibration to a smooth projective curve,such that each fiber is a singular curve.展开更多
The transfer function of the microring resonator is deduced, and the effects of the normalized loss, coupling coefficient and surrounding media on the resonance performance are investigated thoroughly. Utilizing the i...The transfer function of the microring resonator is deduced, and the effects of the normalized loss, coupling coefficient and surrounding media on the resonance performance are investigated thoroughly. Utilizing the improved fused tapering tech- nique and ingenious self-coiling coupling method, a high-quality microring resonator （radius of about 500 I.tm） with larger extinction ratio （〉10 dB） and sharper resonance is designed and fabricated by a segment of continuous sub-micrometer fiber. The microring resonator constructed in this way demonstrates extremely small connection loss with communication fiber in contrast to the planar waveguide technology.展开更多
基金National Natural Science Foundation of China (No.60377010)
文摘We give the characteristic equation of a W-type fiber by solving Maxwell's equations along with boundary conditions at the interfaces. The cutoff condition of the fundamental mode is examined,and a novel W-type fiber working in S-band is designed.
基金supported by the National Natural Science Foundation of China (No. 10901037)the Doctoral Program Foundation of the Ministry of Education of China (No. 20090071120004)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry
文摘The author gives a characterization of counterexamples to the Kodaira-Ramanujam vanishing theorem on smooth projective surfaces in positive characteristic.More precisely,it is reproved that if there is a counterexample to the Kodaira-Ramanujam vanishing theorem on a smooth projective surface X in positive characteristic,then X is either a quasi-elliptic surface of Kodaira dimension 1 or a surface of general type.Furthermore,it is proved that up to blow-ups,X admits a fibration to a smooth projective curve,such that each fiber is a singular curve.
基金supported by the National Natural Science Foundation of China(Nos.61007007and11002018)
文摘The transfer function of the microring resonator is deduced, and the effects of the normalized loss, coupling coefficient and surrounding media on the resonance performance are investigated thoroughly. Utilizing the improved fused tapering tech- nique and ingenious self-coiling coupling method, a high-quality microring resonator （radius of about 500 I.tm） with larger extinction ratio （〉10 dB） and sharper resonance is designed and fabricated by a segment of continuous sub-micrometer fiber. The microring resonator constructed in this way demonstrates extremely small connection loss with communication fiber in contrast to the planar waveguide technology.
