A new device of two parallel distributed feedback （DFB） lasers integrated monolithically with Y-branch waveguide coupler was fabricated by means of quantum well intermixing. Optical microwave signal was generated in...A new device of two parallel distributed feedback （DFB） lasers integrated monolithically with Y-branch waveguide coupler was fabricated by means of quantum well intermixing. Optical microwave signal was generated in the Y-branch waveguide coupler through frequency beating of the two laser modes coming from two DFB laser in parallel, which had a small difference in frequency. Continuous rapid tuning of optical microwave signal from 13 to 42 GHz were realized by adjusting independently the driving currents injected into the two DFB lasers.展开更多
In recent years, the high density plasma in the range of 10^19～ 10^20m^-3 have been operated in large or middle tokamak device in the world. A muhichannel far infrared interferometer for profile measurement of plasma...In recent years, the high density plasma in the range of 10^19～ 10^20m^-3 have been operated in large or middle tokamak device in the world. A muhichannel far infrared interferometer for profile measurement of plasma density on HL-2A divertor tokamak is being developed, however the design of the interferometer will appear many new problem in face of experimental environment of the HL-2A divertor device, such as how to make both transmission and arrangement of optics of the interferometer, the effect of electromo- tive force on device and how about the vibration etc. According to the eight windows setting on the largest flange of the device we have to design a Michelson-type FIR laser interferometer with 8 probing channels and eight concave mirrors must be attached it to the inner wall of the vacuum vessel of the device. Therefore, there are many problems should be taken into account to resolve, for example, （ 1 ） the vibration-proof consider for muhichannel interferometer and HCN laser, （2） the stabilization and reliability of the mirror frame uum vessel, the mirrors, hanging on internal wall of vachow to prevent the sputtering to （3） the vacuum seal of the windows and the design of mobile seal for the shutter to avoid the sputter coating of plasma,展开更多
基金Project supported by the National Natural Science Foundation of China （Grant No 90401025）. Acknowledgments The authors are grateful to the Multiple-function 0ptoelectronic Integration group, Institute of Semiconductors, CAS for sponsoring this project. We extend our thanks to Professor Wang Zi-Yu of Peking University for microwave signal testing.
文摘A new device of two parallel distributed feedback （DFB） lasers integrated monolithically with Y-branch waveguide coupler was fabricated by means of quantum well intermixing. Optical microwave signal was generated in the Y-branch waveguide coupler through frequency beating of the two laser modes coming from two DFB laser in parallel, which had a small difference in frequency. Continuous rapid tuning of optical microwave signal from 13 to 42 GHz were realized by adjusting independently the driving currents injected into the two DFB lasers.
文摘In recent years, the high density plasma in the range of 10^19～ 10^20m^-3 have been operated in large or middle tokamak device in the world. A muhichannel far infrared interferometer for profile measurement of plasma density on HL-2A divertor tokamak is being developed, however the design of the interferometer will appear many new problem in face of experimental environment of the HL-2A divertor device, such as how to make both transmission and arrangement of optics of the interferometer, the effect of electromo- tive force on device and how about the vibration etc. According to the eight windows setting on the largest flange of the device we have to design a Michelson-type FIR laser interferometer with 8 probing channels and eight concave mirrors must be attached it to the inner wall of the vacuum vessel of the device. Therefore, there are many problems should be taken into account to resolve, for example, （ 1 ） the vibration-proof consider for muhichannel interferometer and HCN laser, （2） the stabilization and reliability of the mirror frame uum vessel, the mirrors, hanging on internal wall of vachow to prevent the sputtering to （3） the vacuum seal of the windows and the design of mobile seal for the shutter to avoid the sputter coating of plasma,
