In this study,we show how a static magnetic field can control photon-induced electron transport through a quantum dot system coupled to a photon cavity.The quantum dot system is connected to two electron reservoirs an...In this study,we show how a static magnetic field can control photon-induced electron transport through a quantum dot system coupled to a photon cavity.The quantum dot system is connected to two electron reservoirs and exposed to an external perpendicular static magnetic field.The propagation of electrons through the system is thus influenced by the static magnetic and the dynamic photon fields.It is observed that the photon cavity forms photon replica states controlling electron transport in the system.If the photon field has more energy than the cyclotron energy,then the photon field is dominant in the electron transport.Consequently,the electron transport is enhanced due to activation of photon replica states.By contrast,the electron transport is suppressed in the system when the photon energy is smaller than the cyclotron energy.展开更多
A new type ultraflattened dispersion square-lattice photonic crystal fiber with two different air-hole diameters in cladding region is proposed and the dispersion is investigated using a compact 2-D finite difference ...A new type ultraflattened dispersion square-lattice photonic crystal fiber with two different air-hole diameters in cladding region is proposed and the dispersion is investigated using a compact 2-D finite difference frequency domain method with the anisotropic perfectly matched layers (PML) absorbing boundary conditions. Through numerical simulation and opti- mizing the geometrical parameters, we find that the photonic crystal fibers proposed can realize ultraflattened dispersion of 0±0.06 ps/(km·nm) in wavelength range of 1.375 μm to 1.605 μm, which is more flat than that of triangular PCF, and the confinement loss is as low as about 0.01 dB/km at wavelength of 1.55 μm.展开更多
The Brillouin gain properties in a double-clad As2Se3 photonic crystal fiber（PCF）are simulated based on the finite-element method（FEM）.The results indicate that the Brillouin gain spectrum（BGS）of our proposed ch...The Brillouin gain properties in a double-clad As2Se3 photonic crystal fiber（PCF）are simulated based on the finite-element method（FEM）.The results indicate that the Brillouin gain spectrum（BGS）of our proposed chalcogenide PCF exhibits a multipeaked behavior and has a high Brillouin gain coefficient.We also find that a larger size of inner cladding air holes will lead to a more pronounced second peak in the BGS.On the other hand,the size of the outer cladding has nearly no effect on the BGS behavior.Through these results,one can tailor the Stimulated Brillouin scattering effect in PCFs for a wide range of applications.展开更多
Through doping liquid crystals into the core region, we propose a kind of seven-core photonic crystal fiber（PCF）which can achieve mode shaping and temperature sensing simultaneously in the communication window of1.1...Through doping liquid crystals into the core region, we propose a kind of seven-core photonic crystal fiber（PCF）which can achieve mode shaping and temperature sensing simultaneously in the communication window of1.1–1.7 μm. To the best of our knowledge, this is the first time that the function of seven-core PCFs as temperature sensors is investigated. By using the full vectorial finite element method, the characteristics of the fiber with the temperature, such as the effective mode area, the waveguide dispersion, and the confinement loss, are analyzed. This kind of PCF can be competitive in providing temperature sensing in multi-core PCF lasers.展开更多
基金the Icelandic Research and Instruments Funds for financial supportthe Research Fund of the University of Iceland
文摘In this study,we show how a static magnetic field can control photon-induced electron transport through a quantum dot system coupled to a photon cavity.The quantum dot system is connected to two electron reservoirs and exposed to an external perpendicular static magnetic field.The propagation of electrons through the system is thus influenced by the static magnetic and the dynamic photon fields.It is observed that the photon cavity forms photon replica states controlling electron transport in the system.If the photon field has more energy than the cyclotron energy,then the photon field is dominant in the electron transport.Consequently,the electron transport is enhanced due to activation of photon replica states.By contrast,the electron transport is suppressed in the system when the photon energy is smaller than the cyclotron energy.
基金supported by the National Natural ScienceFoundation of China (Grant Nos. 60637010 and 60671036)the National Basic Research Program of China (Grant No.2007CB310403).
文摘A new type ultraflattened dispersion square-lattice photonic crystal fiber with two different air-hole diameters in cladding region is proposed and the dispersion is investigated using a compact 2-D finite difference frequency domain method with the anisotropic perfectly matched layers (PML) absorbing boundary conditions. Through numerical simulation and opti- mizing the geometrical parameters, we find that the photonic crystal fibers proposed can realize ultraflattened dispersion of 0±0.06 ps/(km·nm) in wavelength range of 1.375 μm to 1.605 μm, which is more flat than that of triangular PCF, and the confinement loss is as low as about 0.01 dB/km at wavelength of 1.55 μm.
基金supported by the International Cooperation Projects between China and Singapore under Grant No.2009DFA12640
文摘The Brillouin gain properties in a double-clad As2Se3 photonic crystal fiber（PCF）are simulated based on the finite-element method（FEM）.The results indicate that the Brillouin gain spectrum（BGS）of our proposed chalcogenide PCF exhibits a multipeaked behavior and has a high Brillouin gain coefficient.We also find that a larger size of inner cladding air holes will lead to a more pronounced second peak in the BGS.On the other hand,the size of the outer cladding has nearly no effect on the BGS behavior.Through these results,one can tailor the Stimulated Brillouin scattering effect in PCFs for a wide range of applications.
基金supported by the Natural Science Foundation of China with under Grant No.61475029
文摘Through doping liquid crystals into the core region, we propose a kind of seven-core photonic crystal fiber（PCF）which can achieve mode shaping and temperature sensing simultaneously in the communication window of1.1–1.7 μm. To the best of our knowledge, this is the first time that the function of seven-core PCFs as temperature sensors is investigated. By using the full vectorial finite element method, the characteristics of the fiber with the temperature, such as the effective mode area, the waveguide dispersion, and the confinement loss, are analyzed. This kind of PCF can be competitive in providing temperature sensing in multi-core PCF lasers.
