A quantum well intermixing（QW1） investigation on double quantum well（DQW） structure with two different emitting wavelength caused by phosphorus ion implantation and following rapid thermal annealing （RTA） was ca...A quantum well intermixing（QW1） investigation on double quantum well（DQW） structure with two different emitting wavelength caused by phosphorus ion implantation and following rapid thermal annealing （RTA） was carried out by means of photoluminescence（PL）. The ion implantation was performed at the energy of 120 keV with the dose ranging from 1 × 10^11cm^-2 to 1× 10^14cm^-2. The RTA was performed at the temperature of 700 ℃ for 30 s under pure nitrogen protection. The PL measurement implied that the band gap blue-shift from the upper well increases with the ion dose faster than that from lower well and the PL peaks from both QWs remained well separated under the lower dose implantation（-1 × 10^11cm^-2） indicating that the implant vacancy distribution affects the QWl. When the ion dose is over - 1 × 10^12cm^-2, the band gap blue-shift from both wells increases with the ion dose and finally the two peaks merge together as one peak indicating the ion implantation caused a total intermixing of both quantum wells.展开更多
Due to the zero dispersion point at 1.3μm in optical fibres, 1.3-μm InGaAsP/InP laser diodes have become main light sources in fibre communication systems recently. Influences of quantum noises on direct-modulated p...Due to the zero dispersion point at 1.3μm in optical fibres, 1.3-μm InGaAsP/InP laser diodes have become main light sources in fibre communication systems recently. Influences of quantum noises on direct-modulated properties of single-mode 1.3-μm InGaAsP/InP laser diodes are investigated in this article. Considering the carrier and photon noises and the cross-correlation between the two noises, the power spectrum of the photon density and the signal-to-noise ratio （SNR） of the direct-modulated single-mode laser system are calculated using the linear approximation method. We find that the stochastic resonance （SR） always appears in the dependence of the SNR on the bias current density, and is strongly affected by the cross-correlation coefficient between the carrier and photon noises, the frequency of modulation signal, and the photon lifetime in the laser cavity. Hence, it is promising to use the SR mechanism to enhance the SNR of direct-modulated InGaAsP/InP laser diodes and improve the quality of optical fibre communication systems.展开更多
We present a novel superluminescent diode （SLD） with high optical performances for hardened neutron irradiation. The degradation of the light output from the SLDs is caused by a reduction of the minority carrier lif...We present a novel superluminescent diode （SLD） with high optical performances for hardened neutron irradiation. The degradation of the light output from the SLDs is caused by a reduction of the minority carrier lifetime resulting from displacement damage after high-energy neutron irradiation. The SLDs with a higher pre- irradiation light output will be less sensitive to radiation. We have selected an InGaAsP/InP multi-quantum well （MQW） as the active region structure for its performance, its high optical gain and minute active region. Graded- index separate-confinement-heterostructure （GRIN-SCH） has been applied for the waveguide structure. A specific absorbing region and anti-reflective coatings have been designed and optimized. Moreover, the radiation test results indicate that the SLD with an InGaAsP/InP MQW structure has better neutron hardening ability than the SLD with DH structures after a 6×10^13-1×10^14 n/cm^2 1 MeV neutron irradiation.展开更多
We report the simulation and experimental results of 1.3-μm InGaAsP/InP multiple quantum well （MQW） electro-absorption modulators （EAMs）. In this work, the quantum confined Stark effect of the EAM is system- atic...We report the simulation and experimental results of 1.3-μm InGaAsP/InP multiple quantum well （MQW） electro-absorption modulators （EAMs）. In this work, the quantum confined Stark effect of the EAM is system- atically analyzed through the finite element method. An optimized structure of the 1.3-μm InGaAsP/InP QW EAM is proposed for applications in 100 G ethernet. Then 1.3-μm InGaAsP/InP EAMs with f-3dB bandwidth of over 20 GHz and extinction ratio over 20 dB at 3 V bias voltage are demonstrated.展开更多
Bandgap tuning of the InGaAsP/InP multiple quantum well(MQW)laser structure by the impurity-free vacancy diffusion(IFVD)is investigated using photoluminescence.It has been demonstrated that the effects of the plasma b...Bandgap tuning of the InGaAsP/InP multiple quantum well(MQW)laser structure by the impurity-free vacancy diffusion(IFVD)is investigated using photoluminescence.It has been demonstrated that the effects of the plasma bombardment to the sample surface involved in the IFVD technique can enhance the intermixing of the InGaAsP/InP MQW laser structure.The reliability of the IFVD technique,particularly the effects of the surface decomposition and the intrinsic defects formed in the growth or preparation of the wafer,has been discussed.展开更多
A system of an add-drop microring resonator integrated with a sampled grating distributed feedback （SG-DFB） is investigated via modeling and simulation with the time-domain traveling wave （TDTW） method. The propos...A system of an add-drop microring resonator integrated with a sampled grating distributed feedback （SG-DFB） is investigated via modeling and simulation with the time-domain traveling wave （TDTW） method. The proposed microring resonator comprises a SiO2 waveguide integrated with an InGaAsP/InP SG-DFB, and the SiO2 waveguide consists of a silicon core having a refractive index of 3.48 and Kerr co- efficient of 4.5 × 10^-18 m2/W. The SG-DFB consists of a series of grating bursts that are constructed using a periodic apodization function with a burst spacing in the grating of 45 μm, a burst length of 5 μm, and I0 bursts across the total length of the SG-DBR. Transmission results of the through and drop port of the microring resonator show the significant capacity enhancement of the generated center wavelengths. The Q-factor of the microring resonator system, defined as the center wavelength （λ0） divided by 3 dB FWHM, without and with integration with the SG-DFB is calculated as 1.93 × 10^5 and 2.87 × 10^5, respectively. Analysis of the dispersion of the system reveals that increasing the wavelength results in a decrease of the dispersion. The higher capacity and efficiency are the advantages of integrating the microring resonator and the InGaAsP/InP SG-DFB.展开更多
基金Supported by the National Natural Science Foundation of China(NSFC)(62174166,11991063,U2241219)Shanghai Municipal Science and Technology Major Project(2019SHZDZX01,22JC1402902)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB43010200)。
文摘A quantum well intermixing（QW1） investigation on double quantum well（DQW） structure with two different emitting wavelength caused by phosphorus ion implantation and following rapid thermal annealing （RTA） was carried out by means of photoluminescence（PL）. The ion implantation was performed at the energy of 120 keV with the dose ranging from 1 × 10^11cm^-2 to 1× 10^14cm^-2. The RTA was performed at the temperature of 700 ℃ for 30 s under pure nitrogen protection. The PL measurement implied that the band gap blue-shift from the upper well increases with the ion dose faster than that from lower well and the PL peaks from both QWs remained well separated under the lower dose implantation（-1 × 10^11cm^-2） indicating that the implant vacancy distribution affects the QWl. When the ion dose is over - 1 × 10^12cm^-2, the band gap blue-shift from both wells increases with the ion dose and finally the two peaks merge together as one peak indicating the ion implantation caused a total intermixing of both quantum wells.
基金Project supported by the National Natural Science Foundation of China （Grant No 10275025）.
文摘Due to the zero dispersion point at 1.3μm in optical fibres, 1.3-μm InGaAsP/InP laser diodes have become main light sources in fibre communication systems recently. Influences of quantum noises on direct-modulated properties of single-mode 1.3-μm InGaAsP/InP laser diodes are investigated in this article. Considering the carrier and photon noises and the cross-correlation between the two noises, the power spectrum of the photon density and the signal-to-noise ratio （SNR） of the direct-modulated single-mode laser system are calculated using the linear approximation method. We find that the stochastic resonance （SR） always appears in the dependence of the SNR on the bias current density, and is strongly affected by the cross-correlation coefficient between the carrier and photon noises, the frequency of modulation signal, and the photon lifetime in the laser cavity. Hence, it is promising to use the SR mechanism to enhance the SNR of direct-modulated InGaAsP/InP laser diodes and improve the quality of optical fibre communication systems.
文摘We present a novel superluminescent diode （SLD） with high optical performances for hardened neutron irradiation. The degradation of the light output from the SLDs is caused by a reduction of the minority carrier lifetime resulting from displacement damage after high-energy neutron irradiation. The SLDs with a higher pre- irradiation light output will be less sensitive to radiation. We have selected an InGaAsP/InP multi-quantum well （MQW） as the active region structure for its performance, its high optical gain and minute active region. Graded- index separate-confinement-heterostructure （GRIN-SCH） has been applied for the waveguide structure. A specific absorbing region and anti-reflective coatings have been designed and optimized. Moreover, the radiation test results indicate that the SLD with an InGaAsP/InP MQW structure has better neutron hardening ability than the SLD with DH structures after a 6×10^13-1×10^14 n/cm^2 1 MeV neutron irradiation.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61274046,61474111 and 61321063the National High-Technology Research and Development Program of China under Grant No 2013AA014202
文摘We report the simulation and experimental results of 1.3-μm InGaAsP/InP multiple quantum well （MQW） electro-absorption modulators （EAMs）. In this work, the quantum confined Stark effect of the EAM is system- atically analyzed through the finite element method. An optimized structure of the 1.3-μm InGaAsP/InP QW EAM is proposed for applications in 100 G ethernet. Then 1.3-μm InGaAsP/InP EAMs with f-3dB bandwidth of over 20 GHz and extinction ratio over 20 dB at 3 V bias voltage are demonstrated.
基金Supported by the National Natural Science Foundation of China under Grant No.69786001“New Star”program for science and technology in Beijing(Contract No.952870300).
文摘Bandgap tuning of the InGaAsP/InP multiple quantum well(MQW)laser structure by the impurity-free vacancy diffusion(IFVD)is investigated using photoluminescence.It has been demonstrated that the effects of the plasma bombardment to the sample surface involved in the IFVD technique can enhance the intermixing of the InGaAsP/InP MQW laser structure.The reliability of the IFVD technique,particularly the effects of the surface decomposition and the intrinsic defects formed in the growth or preparation of the wafer,has been discussed.
基金Grant number LRGS(2015)NGOD/UM/KPT,RU007/2015 and RUG OF UTM,09H77 and 10J97 from the university of Malaya (UM) and Universiti Teknologi Malaysia (UTM)
文摘A system of an add-drop microring resonator integrated with a sampled grating distributed feedback （SG-DFB） is investigated via modeling and simulation with the time-domain traveling wave （TDTW） method. The proposed microring resonator comprises a SiO2 waveguide integrated with an InGaAsP/InP SG-DFB, and the SiO2 waveguide consists of a silicon core having a refractive index of 3.48 and Kerr co- efficient of 4.5 × 10^-18 m2/W. The SG-DFB consists of a series of grating bursts that are constructed using a periodic apodization function with a burst spacing in the grating of 45 μm, a burst length of 5 μm, and I0 bursts across the total length of the SG-DBR. Transmission results of the through and drop port of the microring resonator show the significant capacity enhancement of the generated center wavelengths. The Q-factor of the microring resonator system, defined as the center wavelength （λ0） divided by 3 dB FWHM, without and with integration with the SG-DFB is calculated as 1.93 × 10^5 and 2.87 × 10^5, respectively. Analysis of the dispersion of the system reveals that increasing the wavelength results in a decrease of the dispersion. The higher capacity and efficiency are the advantages of integrating the microring resonator and the InGaAsP/InP SG-DFB.
