The 975 nm multimode diode lasers with high-order surface Bragg diffraction gratings have been simulated and calcu-lated using the 2D finite difference time domain(FDTD)algorithm and the scattering matrix method(SMM)....The 975 nm multimode diode lasers with high-order surface Bragg diffraction gratings have been simulated and calcu-lated using the 2D finite difference time domain(FDTD)algorithm and the scattering matrix method(SMM).The periods and etch depth of the grating parameters have been optimized.A board area laser diode(BA-LD)with high-order diffraction grat-ings has been designed and fabricated.At output powers up to 10.5 W,the measured spectral width of full width at half maxi-mum(FWHM)is less than 0.5 nm.The results demonstrate that the designed high-order surface gratings can effectively nar-row the spectral width of multimode semiconductor lasers at high output power.展开更多
Output power and reliability are the most important characteristic parameters of semiconductor lasers.However,catas-trophic optical damage(COD),which usually occurs on the cavity surface,will seriously damage the furt...Output power and reliability are the most important characteristic parameters of semiconductor lasers.However,catas-trophic optical damage(COD),which usually occurs on the cavity surface,will seriously damage the further improvement of the output power and affect the reliability.To improve the anti-optical disaster ability of the cavity surface,a non-absorption window(NAW)is adopted for the 915 nm InGaAsP/GaAsP single-quantum well semiconductor laser using quantum well mix-ing(QWI)induced by impurity-free vacancy.Both the principle and the process of point defect diffusion are described in detail in this paper.We also studied the effects of annealing temperature,annealing time,and the thickness of SiO_(2) film on the quan-tum well mixing in a semiconductor laser with a primary epitaxial structure,which is distinct from the previous structures.We found that when compared with the complete epitaxial structure,the blue shift of the semiconductor laser with the primary epi-taxial structure is larger under the same conditions.To obtain the appropriate blue shift window,the primary epitaxial struc-ture can use a lower annealing temperature and shorter annealing time.In addition,the process is less expensive.We also pro-vide references for upcoming device fabrication.展开更多
The optical catastrophic damage that usually occurs at the cavity surface of semiconductor lasers has become the main bottleneck affecting the improvement of laser output power and long-term reliability.To improve the...The optical catastrophic damage that usually occurs at the cavity surface of semiconductor lasers has become the main bottleneck affecting the improvement of laser output power and long-term reliability.To improve the output power of 680 nm AlGaInP/GaInP quantum well red semiconductor lasers,Si-Si_(3)N_(4)composited dielectric layers are used to induce its quantum wells to be intermixed at the cavity surface to make a non-absorption window.Si with a thickness of 100 nm and Si_(3)N_(4)with a thickness of 100 nm were grown on the surface of the epitaxial wafer by magnetron sputtering and PECVD as diffusion source and driving source,respectively.Compared with traditional Si impurity induced quantum well intermixing,this paper realizes the blue shift of 54.8 nm in the nonabsorbent window region at a lower annealing temperature of 600 ℃ and annealing time of 10 min.Under this annealing condition,the wavelength of the gain luminescence region basically does not shift to short wavelength,and the surface morphology of the whole epitaxial wafer remains fine after annealing.The application of this process condition can reduce the difficulty of production and save cost,which provides an effective method for upcoming fabrication.展开更多
We use traveling wave coupling theory to investigate the time domain characteristics of tapered semiconductor lasers with DBR gratings.We analyze the influence of the length of second order gratings on the power and s...We use traveling wave coupling theory to investigate the time domain characteristics of tapered semiconductor lasers with DBR gratings.We analyze the influence of the length of second order gratings on the power and spectrum of output light,and optimizing the length of gratings,in order to reduce the mode competition effect in the device,and obtain the high power output light wave with good longitudinal mode characteristics.展开更多
Based on the high-speed development of the fiber laser in recent years, the development of researching 915 nm semiconductor laser as main pumping sources of the fiber laser is at a high speed. Because the beam quality...Based on the high-speed development of the fiber laser in recent years, the development of researching 915 nm semiconductor laser as main pumping sources of the fiber laser is at a high speed. Because the beam quality of the laser diode is very poor, the 915 nm laser diode is generally based on optical fiber coupling module to output the laser. Using the beam-shaping and fiber-coupling technology to improve the quality of output beam light, we present a kind of high-power and high-brightness semiconductor laser module, which can output 13.22 W through the optical fiber. Based on 915 nm GaAs semiconductor laser diode which has output power of 13.91 W, we describe a thoroughly detailed procedure for reshaping the beam output from the semiconductor laser diode and coupling the beam into the optical fiber of which the core diameter is 105 μm and the numerical aperture is 0.18. We get 13.22 W from the output fiber of the module at 14.5 A, the coupling efficiency of the whole module is 95.03% and the brightness is 1.5 MW/cm^2 -str. The output power of the single chip semiconductor laser module achieves the advanced level in the domestic use.展开更多
The high power and low internal loss 1.06 μm InGaAs/GaAsP quantum well lasers with asymmetric waveguide structure were designed and fabricated. For a 4000 μm cavity length and 100 μm stripe width device,the maximum...The high power and low internal loss 1.06 μm InGaAs/GaAsP quantum well lasers with asymmetric waveguide structure were designed and fabricated. For a 4000 μm cavity length and 100 μm stripe width device,the maximum output power and conversion efficiency of the device are 7.13 W and 56.4%, respectively. The cavity length dependence of the threshold current density and conversion efficiency have been investigated theoretically and experimentally; the laser diode with 4000 μm cavity length shows better characteristics than that with 3000 and 4500 μm cavity length: the threshold current density is 132.5 A/cm^2, the slope efficiency of 1.00 W/A and the junction temperature of 15.62 K were achieved.展开更多
The thermal characteristics of high-power AlGaAs/GaAs laser diodes(LDs) at high current(2-10 A)are studied with electrical transient method.The temperature rise increases linearly with the current.The thermal resistan...The thermal characteristics of high-power AlGaAs/GaAs laser diodes(LDs) at high current(2-10 A)are studied with electrical transient method.The temperature rise increases linearly with the current.The thermal resistance of chip is the largest proportion of total thermal resistance.By increasing the width of the chip from 500 to 800 fim,the temperature rise and thermal resistance decrease by 8.5%and 8.8%,respectively.展开更多
基金supported by the National Key R&D Program of China,No.2022YFB4601201.
文摘The 975 nm multimode diode lasers with high-order surface Bragg diffraction gratings have been simulated and calcu-lated using the 2D finite difference time domain(FDTD)algorithm and the scattering matrix method(SMM).The periods and etch depth of the grating parameters have been optimized.A board area laser diode(BA-LD)with high-order diffraction grat-ings has been designed and fabricated.At output powers up to 10.5 W,the measured spectral width of full width at half maxi-mum(FWHM)is less than 0.5 nm.The results demonstrate that the designed high-order surface gratings can effectively nar-row the spectral width of multimode semiconductor lasers at high output power.
基金This work was supported by the National Natural Science Foundation of China(NNSFC)(Grant No.62174154).
文摘Output power and reliability are the most important characteristic parameters of semiconductor lasers.However,catas-trophic optical damage(COD),which usually occurs on the cavity surface,will seriously damage the further improvement of the output power and affect the reliability.To improve the anti-optical disaster ability of the cavity surface,a non-absorption window(NAW)is adopted for the 915 nm InGaAsP/GaAsP single-quantum well semiconductor laser using quantum well mix-ing(QWI)induced by impurity-free vacancy.Both the principle and the process of point defect diffusion are described in detail in this paper.We also studied the effects of annealing temperature,annealing time,and the thickness of SiO_(2) film on the quan-tum well mixing in a semiconductor laser with a primary epitaxial structure,which is distinct from the previous structures.We found that when compared with the complete epitaxial structure,the blue shift of the semiconductor laser with the primary epi-taxial structure is larger under the same conditions.To obtain the appropriate blue shift window,the primary epitaxial struc-ture can use a lower annealing temperature and shorter annealing time.In addition,the process is less expensive.We also pro-vide references for upcoming device fabrication.
基金supported by the National Natural Science Foundation of China(NNSFC)(Grant No.62174154).
文摘The optical catastrophic damage that usually occurs at the cavity surface of semiconductor lasers has become the main bottleneck affecting the improvement of laser output power and long-term reliability.To improve the output power of 680 nm AlGaInP/GaInP quantum well red semiconductor lasers,Si-Si_(3)N_(4)composited dielectric layers are used to induce its quantum wells to be intermixed at the cavity surface to make a non-absorption window.Si with a thickness of 100 nm and Si_(3)N_(4)with a thickness of 100 nm were grown on the surface of the epitaxial wafer by magnetron sputtering and PECVD as diffusion source and driving source,respectively.Compared with traditional Si impurity induced quantum well intermixing,this paper realizes the blue shift of 54.8 nm in the nonabsorbent window region at a lower annealing temperature of 600 ℃ and annealing time of 10 min.Under this annealing condition,the wavelength of the gain luminescence region basically does not shift to short wavelength,and the surface morphology of the whole epitaxial wafer remains fine after annealing.The application of this process condition can reduce the difficulty of production and save cost,which provides an effective method for upcoming fabrication.
文摘We use traveling wave coupling theory to investigate the time domain characteristics of tapered semiconductor lasers with DBR gratings.We analyze the influence of the length of second order gratings on the power and spectrum of output light,and optimizing the length of gratings,in order to reduce the mode competition effect in the device,and obtain the high power output light wave with good longitudinal mode characteristics.
文摘Based on the high-speed development of the fiber laser in recent years, the development of researching 915 nm semiconductor laser as main pumping sources of the fiber laser is at a high speed. Because the beam quality of the laser diode is very poor, the 915 nm laser diode is generally based on optical fiber coupling module to output the laser. Using the beam-shaping and fiber-coupling technology to improve the quality of output beam light, we present a kind of high-power and high-brightness semiconductor laser module, which can output 13.22 W through the optical fiber. Based on 915 nm GaAs semiconductor laser diode which has output power of 13.91 W, we describe a thoroughly detailed procedure for reshaping the beam output from the semiconductor laser diode and coupling the beam into the optical fiber of which the core diameter is 105 μm and the numerical aperture is 0.18. We get 13.22 W from the output fiber of the module at 14.5 A, the coupling efficiency of the whole module is 95.03% and the brightness is 1.5 MW/cm^2 -str. The output power of the single chip semiconductor laser module achieves the advanced level in the domestic use.
文摘The high power and low internal loss 1.06 μm InGaAs/GaAsP quantum well lasers with asymmetric waveguide structure were designed and fabricated. For a 4000 μm cavity length and 100 μm stripe width device,the maximum output power and conversion efficiency of the device are 7.13 W and 56.4%, respectively. The cavity length dependence of the threshold current density and conversion efficiency have been investigated theoretically and experimentally; the laser diode with 4000 μm cavity length shows better characteristics than that with 3000 and 4500 μm cavity length: the threshold current density is 132.5 A/cm^2, the slope efficiency of 1.00 W/A and the junction temperature of 15.62 K were achieved.
基金the National Natural Science Foundation of China(31901194)the Joint Funds of National Natural Science Foundation of China and Henan Province of China(U1904204).
文摘The thermal characteristics of high-power AlGaAs/GaAs laser diodes(LDs) at high current(2-10 A)are studied with electrical transient method.The temperature rise increases linearly with the current.The thermal resistance of chip is the largest proportion of total thermal resistance.By increasing the width of the chip from 500 to 800 fim,the temperature rise and thermal resistance decrease by 8.5%and 8.8%,respectively.
