A thermally tuned multi-channel interference widely tunable semiconductor laser is designed and demonstrated,for the first time to our knowledge,that realizes a tuning range of more than 45 nm,side-mode suppression ra...A thermally tuned multi-channel interference widely tunable semiconductor laser is designed and demonstrated,for the first time to our knowledge,that realizes a tuning range of more than 45 nm,side-mode suppression ratios up to 56 d B,and Lorentzian linewidth below 160 k Hz.Al Ga In As multiple quantum wells(MQWs)were used to reduce linewidth,which have a lower linewidth enhancement factor compared with In Ga As P MQWs.To decrease the power consumption of micro-heaters,air gaps were fabricated below the arm phase sections.For a 75μm long suspended thermal tuning waveguide,about 6.3 m W micro-heater tuning power is needed for a 2πround-trip phase change.Total micro-heater tuning power required is less than 50 m W across the whole tuning range,which is lower than that of the reported thermally tuned tunable semiconductor lasers.展开更多
We propose a design of single-mode orbital angular momentum(OAM) beam laser with high direct-modulation bandwidth. It is a microcylinder/microring cavity interacted with two types of second-order gratings: the complex...We propose a design of single-mode orbital angular momentum(OAM) beam laser with high direct-modulation bandwidth. It is a microcylinder/microring cavity interacted with two types of second-order gratings: the complex top grating containing the real part and the imaginary part modulations and the side grating. The side grating etched on the periphery of the microcylinder/microring cavity can select a whispering gallery mode with a specific azimuthal mode number, while the complex top grating can scatter the lasing mode with travelling-wave pattern vertically. With the cooperation of the gratings, the laser works with a single mode and emits radially polarized OAM beams. With an asymmetrical pad metal on the top of the cavity, the OAM on-chip laser can firstly be directly modulated with electrical pumping. Due to the small active volume, the laser with low threshold current is predicted to have a high direct modulation bandwidth about 29 GHz with the bias current of ten times the threshold from the simulation. The semiconductor OAM laser can be rather easily realized at different wavelengths such as the O band, C band, and L band.展开更多
基金National Key Research and Development Program of China(2018YFB2201201)China Postdoctoral Science Foundation(2018M642824)+1 种基金National Natural Science Foundation of China(61675077,61904064)State Key Laboratory on Integrated Optoelectronics(IOSKL2018KF13)。
文摘A thermally tuned multi-channel interference widely tunable semiconductor laser is designed and demonstrated,for the first time to our knowledge,that realizes a tuning range of more than 45 nm,side-mode suppression ratios up to 56 d B,and Lorentzian linewidth below 160 k Hz.Al Ga In As multiple quantum wells(MQWs)were used to reduce linewidth,which have a lower linewidth enhancement factor compared with In Ga As P MQWs.To decrease the power consumption of micro-heaters,air gaps were fabricated below the arm phase sections.For a 75μm long suspended thermal tuning waveguide,about 6.3 m W micro-heater tuning power is needed for a 2πround-trip phase change.Total micro-heater tuning power required is less than 50 m W across the whole tuning range,which is lower than that of the reported thermally tuned tunable semiconductor lasers.
基金supported by the National Key Research and Development Program of China (No.2016YFB0402304)。
文摘We propose a design of single-mode orbital angular momentum(OAM) beam laser with high direct-modulation bandwidth. It is a microcylinder/microring cavity interacted with two types of second-order gratings: the complex top grating containing the real part and the imaginary part modulations and the side grating. The side grating etched on the periphery of the microcylinder/microring cavity can select a whispering gallery mode with a specific azimuthal mode number, while the complex top grating can scatter the lasing mode with travelling-wave pattern vertically. With the cooperation of the gratings, the laser works with a single mode and emits radially polarized OAM beams. With an asymmetrical pad metal on the top of the cavity, the OAM on-chip laser can firstly be directly modulated with electrical pumping. Due to the small active volume, the laser with low threshold current is predicted to have a high direct modulation bandwidth about 29 GHz with the bias current of ten times the threshold from the simulation. The semiconductor OAM laser can be rather easily realized at different wavelengths such as the O band, C band, and L band.
