In this article, we report the first experimental demonstration of the three-phase-shifted （3PS） DFB semiconductor laser with buried heterostructure based on the Reconstruction-Equivalent-Chirp （REC） technique. Th...In this article, we report the first experimental demonstration of the three-phase-shifted （3PS） DFB semiconductor laser with buried heterostructure based on the Reconstruction-Equivalent-Chirp （REC） technique. The simulation results show that the performances of the equivalent 3PS DFB semiconductor laser are nearly the same as those of the true 3PS laser. Compared with the quarter-wave-phase shift （QWS） DFB semiconductor laser, the 3PS DFB semiconductor laser shows better single-longitude-mode （SLM） property even at high injection current with high temperature. However, it only changes the ~un-level sampling structures but the seed grating is uniform using the REC tech- nique. Therefore, its fabrication cost is low.展开更多
In this article,we report the first experimental demonstration of an eight-wavelength λ/8 phased-shifted laser array based on the REC technique in the 1.3 μm wavelength domain.Measurement results exhibit good linear...In this article,we report the first experimental demonstration of an eight-wavelength λ/8 phased-shifted laser array based on the REC technique in the 1.3 μm wavelength domain.Measurement results exhibit good linearity of lasing wavelength with+/-0.35 nm wavelength residual.The SLM property was ensured with SMSRs all larger than 38 dB.Moreover,the directmodulation performance was also tested.The experimental results show that the modulation bandwidth can reach up to 13GHz even at the small injection current of 40 mA and the measured spurious-free dynamic range(SFDR)is up to 87 dB/Hz2/3,which shows good linearity.These measurements show that REC-based λ/8 phased-shifted laser array has good modulation performance and it may find potential application in actual fiber-optic systems.展开更多
A new effect of transient mode competition in directly modulated DFB laser based on equivalent phase-shift （EPS） technique is presented and studied. Since there are multi-order reflections in EPS structure and if th...A new effect of transient mode competition in directly modulated DFB laser based on equivalent phase-shift （EPS） technique is presented and studied. Since there are multi-order reflections in EPS structure and if the 0th order subgrating is properly de- signed, the transient lasing of 0th order will occur during the rising time of the injection current. As a result, transient mode competition between -lst order （main mode） and 0th order will occur accordingly. This can consume redundant carrier and suppress the transient relaxation oscillation, which may be applied in some areas like on-off switching modulation of DFB semiconductor lasers. As an example, an equivalent n phase shift （n-EPS） is carefully designed to realize the effect. In such a laser the 0th order wavelength is in the margin of the material gain region and the -1st order wavelength is around the gain peak, while the stable single longitudinal mode （SLM） operation of the -lst order is guaranteed. The simulation investigation is performed. Good results with suppressed relaxation oscillation and 1.25 Gb/s directly on-off modulation （32 dB extinction ratio） are demonstrated. We believe it provides a new kind of method for on-off switching with high extinction ratio and weak relaxation oscillation.展开更多
A distributed feedback(DFB) semiconductor laser with three phase shifts based on reconstruction equivalent chirp(REC) technology is proposed and investigated numerically.With the combination of multiple phase shifts a...A distributed feedback(DFB) semiconductor laser with three phase shifts based on reconstruction equivalent chirp(REC) technology is proposed and investigated numerically.With the combination of multiple phase shifts and corrugation pitch modulated(CPM) structure,we also propose a novel and more complex structure named dual CPM,which has a flatter light power distribution along the laser cavity compared with the true double phase shifts DFB laser diode(LD),while the P-I curves are nearly the same.The proposed dual CPM structure is also designed and analyzed based on REC technology.The simulation results show that,the DFB semiconductor laser with complex structure such as phase shifts,or even arbitrary variation of the grating period can be achieved equivalently and easily by changing the sampling structure.But its external characteristics are almost the same as those DFB lasers with true phase shifts,or true arbitrary variation of the grating period.The key advantage of the REC technology is that it varies only the sampling structure and keeps the seed grating(actual grating in sampling structure) period constant.So its fabrication needs only low-cost and standard holographic exposure technology.Therefore we believe this method can achieve the high-end and low-cost DFB LD for mass production.展开更多
In this paper,the fabrication of 1.3μm InGaAsP/InP gain-coupled DFB lasers with lossgrating is reported for the first time.A technique of regrowth on corrugated surface usingLPE is developed.By using GaAs as the cove...In this paper,the fabrication of 1.3μm InGaAsP/InP gain-coupled DFB lasers with lossgrating is reported for the first time.A technique of regrowth on corrugated surface usingLPE is developed.By using GaAs as the cover of thermal protection and controlling theamount of the super cooling,high quality epitxial layers on corrugated surface are obtained.The oxide stripe lasers with a stripe width of 20μm are fabricated.Single-mode oscillation isachieved at 1.293μm,and a high single-mode oscillation yield is also obtained.展开更多
报道了一种基于全息曝光技术实现的20波长分布反馈式(DFB)半导体激光器阵列。传统的DFB半导体激光器光栅一般是利用电子束曝光的方式来实现,这种方式精度较高,然而成本昂贵并且非常耗时,不适合大规模生产应用,而全息方式制作容易,成本很...报道了一种基于全息曝光技术实现的20波长分布反馈式(DFB)半导体激光器阵列。传统的DFB半导体激光器光栅一般是利用电子束曝光的方式来实现,这种方式精度较高,然而成本昂贵并且非常耗时,不适合大规模生产应用,而全息方式制作容易,成本很低,适合大规模生产应用。实验结果表明,利用全息曝光技术实现的DFB激光器阵列具有良好的光电特性,激光器阵列的波长偏差在-0.5 nm至0.45 nm,阈值电流在13m A至17 m A,斜效率为0.4 W/A;50 m A偏置电流下,边模抑制比都大于40 d B。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.61090392)the National Hi-Tech Research and Development Program of China("863"Project)(Grant No.2011AA010300)the Key Programs of the Ministry of Education of China(Grant No.20100091110005)
文摘In this article, we report the first experimental demonstration of the three-phase-shifted （3PS） DFB semiconductor laser with buried heterostructure based on the Reconstruction-Equivalent-Chirp （REC） technique. The simulation results show that the performances of the equivalent 3PS DFB semiconductor laser are nearly the same as those of the true 3PS laser. Compared with the quarter-wave-phase shift （QWS） DFB semiconductor laser, the 3PS DFB semiconductor laser shows better single-longitude-mode （SLM） property even at high injection current with high temperature. However, it only changes the ~un-level sampling structures but the seed grating is uniform using the REC tech- nique. Therefore, its fabrication cost is low.
基金supported by the National Natural Science Foundation of China(Grant No.61090392)the National Hi-Tech Research and Development Program of China("863"Project)(Grant No.2011AA010300)the Key Programs of the Ministry of Education of China(Grant No.20100091110005)
文摘In this article,we report the first experimental demonstration of an eight-wavelength λ/8 phased-shifted laser array based on the REC technique in the 1.3 μm wavelength domain.Measurement results exhibit good linearity of lasing wavelength with+/-0.35 nm wavelength residual.The SLM property was ensured with SMSRs all larger than 38 dB.Moreover,the directmodulation performance was also tested.The experimental results show that the modulation bandwidth can reach up to 13GHz even at the small injection current of 40 mA and the measured spurious-free dynamic range(SFDR)is up to 87 dB/Hz2/3,which shows good linearity.These measurements show that REC-based λ/8 phased-shifted laser array has good modulation performance and it may find potential application in actual fiber-optic systems.
基金supported by the National Natural Science Foundation of China(Grant Nos.61306068 and 61435014)the Nature Science Foundation of Jiangsu Province of China(Grant Nos.BK20130585,BK2012058 and BK20140414)National High-Tech R&D Program of China(Grand No.SS2015AA012302)
文摘A new effect of transient mode competition in directly modulated DFB laser based on equivalent phase-shift （EPS） technique is presented and studied. Since there are multi-order reflections in EPS structure and if the 0th order subgrating is properly de- signed, the transient lasing of 0th order will occur during the rising time of the injection current. As a result, transient mode competition between -lst order （main mode） and 0th order will occur accordingly. This can consume redundant carrier and suppress the transient relaxation oscillation, which may be applied in some areas like on-off switching modulation of DFB semiconductor lasers. As an example, an equivalent n phase shift （n-EPS） is carefully designed to realize the effect. In such a laser the 0th order wavelength is in the margin of the material gain region and the -1st order wavelength is around the gain peak, while the stable single longitudinal mode （SLM） operation of the -lst order is guaranteed. The simulation investigation is performed. Good results with suppressed relaxation oscillation and 1.25 Gb/s directly on-off modulation （32 dB extinction ratio） are demonstrated. We believe it provides a new kind of method for on-off switching with high extinction ratio and weak relaxation oscillation.
基金supported by the National Natural Science Foundation of China (60877043)the National High-Tech Research & Development Program of China (2007AA03Z417)the New-Century Excellent Talents Supporting Program of the Ministry of Education of China
文摘A distributed feedback(DFB) semiconductor laser with three phase shifts based on reconstruction equivalent chirp(REC) technology is proposed and investigated numerically.With the combination of multiple phase shifts and corrugation pitch modulated(CPM) structure,we also propose a novel and more complex structure named dual CPM,which has a flatter light power distribution along the laser cavity compared with the true double phase shifts DFB laser diode(LD),while the P-I curves are nearly the same.The proposed dual CPM structure is also designed and analyzed based on REC technology.The simulation results show that,the DFB semiconductor laser with complex structure such as phase shifts,or even arbitrary variation of the grating period can be achieved equivalently and easily by changing the sampling structure.But its external characteristics are almost the same as those DFB lasers with true phase shifts,or true arbitrary variation of the grating period.The key advantage of the REC technology is that it varies only the sampling structure and keeps the seed grating(actual grating in sampling structure) period constant.So its fabrication needs only low-cost and standard holographic exposure technology.Therefore we believe this method can achieve the high-end and low-cost DFB LD for mass production.
基金Supported by National Natural Science Foundation of Chinathe Trans-Century Training Porgramme Foundation for Talents of the State Education Commission.
文摘In this paper,the fabrication of 1.3μm InGaAsP/InP gain-coupled DFB lasers with lossgrating is reported for the first time.A technique of regrowth on corrugated surface usingLPE is developed.By using GaAs as the cover of thermal protection and controlling theamount of the super cooling,high quality epitxial layers on corrugated surface are obtained.The oxide stripe lasers with a stripe width of 20μm are fabricated.Single-mode oscillation isachieved at 1.293μm,and a high single-mode oscillation yield is also obtained.
文摘报道了一种基于全息曝光技术实现的20波长分布反馈式(DFB)半导体激光器阵列。传统的DFB半导体激光器光栅一般是利用电子束曝光的方式来实现,这种方式精度较高,然而成本昂贵并且非常耗时,不适合大规模生产应用,而全息方式制作容易,成本很低,适合大规模生产应用。实验结果表明,利用全息曝光技术实现的DFB激光器阵列具有良好的光电特性,激光器阵列的波长偏差在-0.5 nm至0.45 nm,阈值电流在13m A至17 m A,斜效率为0.4 W/A;50 m A偏置电流下,边模抑制比都大于40 d B。
