A terahertz bandpass filter with the sandwich structure consisting of thermally tunable vanadium dioxide(VO2) thin film,silica substrate and subwavelength rectangular Cu hole arrays is designed and theoretically analy...A terahertz bandpass filter with the sandwich structure consisting of thermally tunable vanadium dioxide(VO2) thin film,silica substrate and subwavelength rectangular Cu hole arrays is designed and theoretically analyzed.The results show that the transmittance of the filter can be actively tuned by controlling the temperature of VO2,the narrow band terahertz(THz) waves with the transmittance from 85.2% to 10.5% can be well selected at the frequency of 1.25 THz when the temperature changes from 50 ℃ to 80 ℃,and the maximum modulation depth of this terahertz bandpass filter can achieve 74.7%.展开更多
Perovskite manganites show exotic functionalities due to the coupling between spin, charge, orbital and lattice, such as metal-insulator transition, colossal magnetoresistance ( CMR ) , charge-orbital order and phas...Perovskite manganites show exotic functionalities due to the coupling between spin, charge, orbital and lattice, such as metal-insulator transition, colossal magnetoresistance ( CMR ) , charge-orbital order and phase separation. Recently, an extraordinary anisotropic magnetoresistance ( AMR ) has been observed in perovskite manganite single crystals. The AMR value is about 2 orders larger than that of the conventional 3E transition metals and alloys, which is attributed to tunable metal-insulator transition temperature modulated by the magnetic field. This result provides a new route for exploring novel AMR materials and their applications.展开更多
基金supported by the National High Technology Research and Development Program of China(No.2011AA010205)the National Natural Science Foundation of China(Nos.61171027 and 10904076)the Tianjin City High School Science&Technology Fund Planning Project(No.20120706)
文摘A terahertz bandpass filter with the sandwich structure consisting of thermally tunable vanadium dioxide(VO2) thin film,silica substrate and subwavelength rectangular Cu hole arrays is designed and theoretically analyzed.The results show that the transmittance of the filter can be actively tuned by controlling the temperature of VO2,the narrow band terahertz(THz) waves with the transmittance from 85.2% to 10.5% can be well selected at the frequency of 1.25 THz when the temperature changes from 50 ℃ to 80 ℃,and the maximum modulation depth of this terahertz bandpass filter can achieve 74.7%.
基金supported by National Natural Science Foundation of China(10874192)
文摘Perovskite manganites show exotic functionalities due to the coupling between spin, charge, orbital and lattice, such as metal-insulator transition, colossal magnetoresistance ( CMR ) , charge-orbital order and phase separation. Recently, an extraordinary anisotropic magnetoresistance ( AMR ) has been observed in perovskite manganite single crystals. The AMR value is about 2 orders larger than that of the conventional 3E transition metals and alloys, which is attributed to tunable metal-insulator transition temperature modulated by the magnetic field. This result provides a new route for exploring novel AMR materials and their applications.