The theoretical optimization of tensile strained InGaAsP/InGaAsP MQW for 1.55μm windows polarization-independent semiconductor optical amplifier is reported.The valence-band structure of the MQW is calculated by usin...The theoretical optimization of tensile strained InGaAsP/InGaAsP MQW for 1.55μm windows polarization-independent semiconductor optical amplifier is reported.The valence-band structure of the MQW is calculated by using k·p method,in which 6×6 Luttinger effective-mass Hamiltonian is taken into account.The polarization dependent optical gain is calculated with various well width,strain,and carrier density.展开更多
An experimental way to analyze the thermal characterization of semiconductor lasers based on spectroscopy method under pulse driving conditions has been developed. By using this way the thermal characteristics of stra...An experimental way to analyze the thermal characterization of semiconductor lasers based on spectroscopy method under pulse driving conditions has been developed. By using this way the thermal characteristics of strain compensated 1.3 μm InAsP/InGaAsP ridge waveguide MQW laser diodes have been investigated. Results show that by measuring and analyzing the lasing spectra under appropriate driving parameters and temperature ranges, the thermal resistance of the laser diodes could be deduced easily. A higher thermal resistance of 640 K/W has been measured on a narrow ridge laser chip without soldering. Other thermal and spectral properties of the lasers have also been measured and discussed.展开更多
Abstract: Transient photocurrents induced by shoft light pulses at lanice-mathed GaAs/Alx.Ga1-x multiple quantum well (MQW) electrodes were studied as a function of electrode potential. Dual exponential photocurrent d...Abstract: Transient photocurrents induced by shoft light pulses at lanice-mathed GaAs/Alx.Ga1-x multiple quantum well (MQW) electrodes were studied as a function of electrode potential. Dual exponential photocurrent decay indents were observed at various potentials. By analysis of the dual exponented decay transients, information on steady state photocurrents (Is). surface collection of photoexcoted mmority cCarriers(GO) and lifetimes of surfaCe states (Ts) was obtained. The kinetic behaviors of photoprocesses at illuminated MQW/electrolyte interface were discussed.展开更多
Structural properties of InxGa_(1−x)N/GaN multi-quantum wells(MQWs)grown on sapphire by metal organic chemical vapor deposition are investigated by synchrotron radiation x-ray diffraction(SRXRD),Rutherford backscatter...Structural properties of InxGa_(1−x)N/GaN multi-quantum wells(MQWs)grown on sapphire by metal organic chemical vapor deposition are investigated by synchrotron radiation x-ray diffraction(SRXRD),Rutherford backscattering/channelling(RBS/C)and high-resolution transmission electron microscopy.The sample consists of eight periods of InxGa_(1−x)N/GaN wells of 2.1 nm thickness and 8.5 nm thickness of GaN barrier,and the results are very close,which verifies the accuracy of the three methods.The indium content in InxGa_(1−x)N/GaN MQWs by SRXRD and RBS/C is estimated,and results are in general the same.By RBS/C random spectra,the indium atomic lattice substitution rate is 94.0%,indicating that almost all indium atoms in InxGa_(1−x)N/GaN MQWs are at substitution,that the indium distribution of each layer in InxGa_(1−x)N/GaN MQWs is very homogeneous and that the InxGa_(1−x)N/GaN MQWs have a very good crystalline quality.It is not accurate to estimate indium content in InxGa_(1−x)N/GaN MQWs by photoluminescence(PL)spectra,because the result from the PL experimental method is very different from the results by the SRXRD and RBS/C experimental methods.展开更多
The transient thermal characteristics of the ridge waveguide InAsP/InGaAsP MQW lasers, especially in various pulse driving conditions,have been simulated by using FEM. The temperature at the active core of the laser v...The transient thermal characteristics of the ridge waveguide InAsP/InGaAsP MQW lasers, especially in various pulse driving conditions,have been simulated by using FEM. The temperature at the active core of the laser versus the time has been calculated as well as pulse width dependence of the apparent thermal resistance.The results show that the thermal characteristics of the lasers are related to both the thermal conductivity and the specific heat of the materials.展开更多
A high power and low distortion 1.31 μm AlGaInAs/InP multiquantum well distributed feedback laser diode (MQW DFB LD) with RWG structure has been developed by MOCVD technique. The fiber output power of butterfly packa...A high power and low distortion 1.31 μm AlGaInAs/InP multiquantum well distributed feedback laser diode (MQW DFB LD) with RWG structure has been developed by MOCVD technique. The fiber output power of butterfly packaged module with optic isolator P f is more than 10 mW, threshold current is in the range of (13~20) mA, slope efficiency, E s>0.30 W/A and side mode suppression ratio, R S,M,S >35 dB. The composite second order, O C,S <-61 dBc and composite triple beat, B C,T <-65 dBc are obtained by test frequencies of (45~550) MHz with 60 PAL channels. In the test conditions the carrier to noise ratio, R C,N >51 dB.展开更多
The effects of different potential well depths, well widths and barrier widths on energy band of multiple quantum well (MQW) structures are discussed in detail based on Kronig-Penny model. The results show that if the...The effects of different potential well depths, well widths and barrier widths on energy band of multiple quantum well (MQW) structures are discussed in detail based on Kronig-Penny model. The results show that if the well and barrier width stay unchanged, the first and second band gaps increase linearly with the well depth. When the well depth is constant, the first and second band gaps increase exponentially with the barrier width in a wide well. However, in narrow well one, the second band gap saturates when the barrier width is wide enough. On condition that the well and barrier have equal width, the first band gap decreases exponentially with well-barrier width while the second gap still shows an exponential increase with the width. These results are insightful for the design of MQW structure optoelectronic devices.展开更多
A comprehensive analysis of multi-quantum-well electroabsorption modulators buried with semi-insulating (SI)-InP is presented. We quantitatively demonstrate that suppression of Zn diffusion into the burying and optica...A comprehensive analysis of multi-quantum-well electroabsorption modulators buried with semi-insulating (SI)-InP is presented. We quantitatively demonstrate that suppression of Zn diffusion into the burying and optical core layers plays a key role in high-speed and high-extinction operation.展开更多
To improve the logic stability of conventional multi-valued logic(MVL) circuits designed with a GaNbased resonate tunneling diode(RTD), we proposed a GaN/InGaN/AlGaN multi-quantum well(MQW) RTD. The proposed RTD...To improve the logic stability of conventional multi-valued logic(MVL) circuits designed with a GaNbased resonate tunneling diode(RTD), we proposed a GaN/InGaN/AlGaN multi-quantum well(MQW) RTD. The proposed RTD was simulated through solving the coupled Schrodinger and Poisson equations in the numerical non-equilibrium Green's function(NEGF) method on the TCAD platform. The proposed RTD was grown layer by layer in epitaxial technologies. Simulated results indicate that its current-voltage characteristic appears to have a wider total negative differential resistance region than those of conventional ones and an obvious hysteresis loop at room temperature. To increase the Al composite of AIGaN barrier layers properly results in increasing of both the total negative differential resistance region width and the hysteresis loop width, which is helpful to improve the logic stability of MVL circuits. Moreover, the complement resonate tunneling transistor pair consisted of the proposed RTDs or the proposed RTD and enhanced mode HEMT controlled RTD8 is capable of generating versatile MVL modes at different supply voltages less than 3.3 V, which is very attractive for implementing more complex MVL function digital integrated circuits and systems with less devices, super high speed linear or nonlinear ADC and voltage sensors with a built-in super high speed ADC function.展开更多
While considerable research has been conducted on the structural principles,fabrication techniques,and photoelectric properties of high-voltage light-emitting diodes(LEDs),their performance in light communication rema...While considerable research has been conducted on the structural principles,fabrication techniques,and photoelectric properties of high-voltage light-emitting diodes(LEDs),their performance in light communication remains underexplored.A high-voltage seriesconnected LED or photodetector(HVS-LED/PD)based on the gallium nitride(GaN)integrated photoelectronic chip is presented in this paper.Multi-quantum wells(MQW)diodes with identical structures are integrated onto a single chip through wafer-scale micro-fabrication techniques and connected in series to construct the HVS-LED/PD.The advantages of the HVS-LED/PD in communication are explored by testing its performance as both a light transmitter and a PD.The series connection enhances the device's 3 dB bandwidth,allowing it to increase from 1.56 MHz to a minimum of 2.16 MHz when functioning as an LED,and from 47.42 kHz to at least 85.83 kHz when operating as a PD.The results demonstrate that the light communication performance of HVS-LED/PD is better than that of a single GaN MQW diode with bandwidth and transmission quantity,which enriches the research of GaN-based high-voltage devices.展开更多
文摘The theoretical optimization of tensile strained InGaAsP/InGaAsP MQW for 1.55μm windows polarization-independent semiconductor optical amplifier is reported.The valence-band structure of the MQW is calculated by using k·p method,in which 6×6 Luttinger effective-mass Hamiltonian is taken into account.The polarization dependent optical gain is calculated with various well width,strain,and carrier density.
文摘An experimental way to analyze the thermal characterization of semiconductor lasers based on spectroscopy method under pulse driving conditions has been developed. By using this way the thermal characteristics of strain compensated 1.3 μm InAsP/InGaAsP ridge waveguide MQW laser diodes have been investigated. Results show that by measuring and analyzing the lasing spectra under appropriate driving parameters and temperature ranges, the thermal resistance of the laser diodes could be deduced easily. A higher thermal resistance of 640 K/W has been measured on a narrow ridge laser chip without soldering. Other thermal and spectral properties of the lasers have also been measured and discussed.
文摘Abstract: Transient photocurrents induced by shoft light pulses at lanice-mathed GaAs/Alx.Ga1-x multiple quantum well (MQW) electrodes were studied as a function of electrode potential. Dual exponential photocurrent decay indents were observed at various potentials. By analysis of the dual exponented decay transients, information on steady state photocurrents (Is). surface collection of photoexcoted mmority cCarriers(GO) and lifetimes of surfaCe states (Ts) was obtained. The kinetic behaviors of photoprocesses at illuminated MQW/electrolyte interface were discussed.
基金by the National Natural Science Foundation of China under Grant No 10875004 and 11005005the National Basic Research Program of China under Grant No 2010CB832904.
文摘Structural properties of InxGa_(1−x)N/GaN multi-quantum wells(MQWs)grown on sapphire by metal organic chemical vapor deposition are investigated by synchrotron radiation x-ray diffraction(SRXRD),Rutherford backscattering/channelling(RBS/C)and high-resolution transmission electron microscopy.The sample consists of eight periods of InxGa_(1−x)N/GaN wells of 2.1 nm thickness and 8.5 nm thickness of GaN barrier,and the results are very close,which verifies the accuracy of the three methods.The indium content in InxGa_(1−x)N/GaN MQWs by SRXRD and RBS/C is estimated,and results are in general the same.By RBS/C random spectra,the indium atomic lattice substitution rate is 94.0%,indicating that almost all indium atoms in InxGa_(1−x)N/GaN MQWs are at substitution,that the indium distribution of each layer in InxGa_(1−x)N/GaN MQWs is very homogeneous and that the InxGa_(1−x)N/GaN MQWs have a very good crystalline quality.It is not accurate to estimate indium content in InxGa_(1−x)N/GaN MQWs by photoluminescence(PL)spectra,because the result from the PL experimental method is very different from the results by the SRXRD and RBS/C experimental methods.
文摘The transient thermal characteristics of the ridge waveguide InAsP/InGaAsP MQW lasers, especially in various pulse driving conditions,have been simulated by using FEM. The temperature at the active core of the laser versus the time has been calculated as well as pulse width dependence of the apparent thermal resistance.The results show that the thermal characteristics of the lasers are related to both the thermal conductivity and the specific heat of the materials.
文摘A high power and low distortion 1.31 μm AlGaInAs/InP multiquantum well distributed feedback laser diode (MQW DFB LD) with RWG structure has been developed by MOCVD technique. The fiber output power of butterfly packaged module with optic isolator P f is more than 10 mW, threshold current is in the range of (13~20) mA, slope efficiency, E s>0.30 W/A and side mode suppression ratio, R S,M,S >35 dB. The composite second order, O C,S <-61 dBc and composite triple beat, B C,T <-65 dBc are obtained by test frequencies of (45~550) MHz with 60 PAL channels. In the test conditions the carrier to noise ratio, R C,N >51 dB.
文摘The effects of different potential well depths, well widths and barrier widths on energy band of multiple quantum well (MQW) structures are discussed in detail based on Kronig-Penny model. The results show that if the well and barrier width stay unchanged, the first and second band gaps increase linearly with the well depth. When the well depth is constant, the first and second band gaps increase exponentially with the barrier width in a wide well. However, in narrow well one, the second band gap saturates when the barrier width is wide enough. On condition that the well and barrier have equal width, the first band gap decreases exponentially with well-barrier width while the second gap still shows an exponential increase with the width. These results are insightful for the design of MQW structure optoelectronic devices.
文摘A comprehensive analysis of multi-quantum-well electroabsorption modulators buried with semi-insulating (SI)-InP is presented. We quantitatively demonstrate that suppression of Zn diffusion into the burying and optical core layers plays a key role in high-speed and high-extinction operation.
基金Project supported by the National Natural Science Foundation of China(Nos.61302009,61571171)
文摘To improve the logic stability of conventional multi-valued logic(MVL) circuits designed with a GaNbased resonate tunneling diode(RTD), we proposed a GaN/InGaN/AlGaN multi-quantum well(MQW) RTD. The proposed RTD was simulated through solving the coupled Schrodinger and Poisson equations in the numerical non-equilibrium Green's function(NEGF) method on the TCAD platform. The proposed RTD was grown layer by layer in epitaxial technologies. Simulated results indicate that its current-voltage characteristic appears to have a wider total negative differential resistance region than those of conventional ones and an obvious hysteresis loop at room temperature. To increase the Al composite of AIGaN barrier layers properly results in increasing of both the total negative differential resistance region width and the hysteresis loop width, which is helpful to improve the logic stability of MVL circuits. Moreover, the complement resonate tunneling transistor pair consisted of the proposed RTDs or the proposed RTD and enhanced mode HEMT controlled RTD8 is capable of generating versatile MVL modes at different supply voltages less than 3.3 V, which is very attractive for implementing more complex MVL function digital integrated circuits and systems with less devices, super high speed linear or nonlinear ADC and voltage sensors with a built-in super high speed ADC function.
基金This work is jointly supported by the National Natural Science Foundation of China under Grant Nos.62004103,62105162,62005130,61827804,62274096,and 61904086the Natural Science Foundation of Jiangsu Province under Grant No.BK20200743+3 种基金the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province under Grant No.22KJA510003the Natural Science Foundation of Nanjing University of Posts and Telecommunications under Grant No.NY223084the“111”project under Grant No.D17018the Postgraduate Research&Practice Innovation Program of Jiangsu Province under Grant No.SJCX230257.
文摘While considerable research has been conducted on the structural principles,fabrication techniques,and photoelectric properties of high-voltage light-emitting diodes(LEDs),their performance in light communication remains underexplored.A high-voltage seriesconnected LED or photodetector(HVS-LED/PD)based on the gallium nitride(GaN)integrated photoelectronic chip is presented in this paper.Multi-quantum wells(MQW)diodes with identical structures are integrated onto a single chip through wafer-scale micro-fabrication techniques and connected in series to construct the HVS-LED/PD.The advantages of the HVS-LED/PD in communication are explored by testing its performance as both a light transmitter and a PD.The series connection enhances the device's 3 dB bandwidth,allowing it to increase from 1.56 MHz to a minimum of 2.16 MHz when functioning as an LED,and from 47.42 kHz to at least 85.83 kHz when operating as a PD.The results demonstrate that the light communication performance of HVS-LED/PD is better than that of a single GaN MQW diode with bandwidth and transmission quantity,which enriches the research of GaN-based high-voltage devices.