A micromachined vertical cavity tunable filter with AlGaAs/GaAs distributed Bragg reflector is presented.This filter can be electrostatic tuning over a range of 28nm with an applied voltage of 7V.
This paper presents an LC VCO with auto-amplitude control （AAC）, in which pMOS FETs are used,and the varactors are directly connected to ground to widen the linear range of Kvco. The AAC circuitry adds little noise ...This paper presents an LC VCO with auto-amplitude control （AAC）, in which pMOS FETs are used,and the varactors are directly connected to ground to widen the linear range of Kvco. The AAC circuitry adds little noise to the VCO but provides it with robust performance over a wide temperature and carrier frequency range.The VCO is fabricated in a chartered 50GHz 0.35μm SiGe BiCMOS process. The measurements show that it has - 127. 27dBc/Hz phase noise at 1MHz offset and a linear gain of 32.4MHz/V between 990MHz and 1.14GHz.The whole circuit draws 6. 6mA current from 5V supply.展开更多
Circular polarization selection of light is an important property of helical micro-nanostructure.The helical thin films fabricated by glancing angle deposition can provide both circular polarization selection and wave...Circular polarization selection of light is an important property of helical micro-nanostructure.The helical thin films fabricated by glancing angle deposition can provide both circular polarization selection and wavelength tuning in this work.Their selective transmissions were depicted in calculations and experiments.The wavelength tuning mechanism was revealed as the relationship between peak wavelength and deposition parameters.Therefore,tunable circular polarization components can be designed according to the mechanism mentioned above and fabricated by glancing angle deposition techniques.Potential applications include tunable optical filters,optical pulse-shapers,biosensors etc.展开更多
文摘A micromachined vertical cavity tunable filter with AlGaAs/GaAs distributed Bragg reflector is presented.This filter can be electrostatic tuning over a range of 28nm with an applied voltage of 7V.
文摘This paper presents an LC VCO with auto-amplitude control （AAC）, in which pMOS FETs are used,and the varactors are directly connected to ground to widen the linear range of Kvco. The AAC circuitry adds little noise to the VCO but provides it with robust performance over a wide temperature and carrier frequency range.The VCO is fabricated in a chartered 50GHz 0.35μm SiGe BiCMOS process. The measurements show that it has - 127. 27dBc/Hz phase noise at 1MHz offset and a linear gain of 32.4MHz/V between 990MHz and 1.14GHz.The whole circuit draws 6. 6mA current from 5V supply.
基金the financial support of the project from the National Natural Science Foundation of China(Grant No.60977042)the Natural Science Foundation of Guangdong Provincial(Grant No.9151027501000070)
文摘Circular polarization selection of light is an important property of helical micro-nanostructure.The helical thin films fabricated by glancing angle deposition can provide both circular polarization selection and wavelength tuning in this work.Their selective transmissions were depicted in calculations and experiments.The wavelength tuning mechanism was revealed as the relationship between peak wavelength and deposition parameters.Therefore,tunable circular polarization components can be designed according to the mechanism mentioned above and fabricated by glancing angle deposition techniques.Potential applications include tunable optical filters,optical pulse-shapers,biosensors etc.
