We report on the performance improvement of long-wave infrared quantum cascade lasers(LWIR QCLs)by studying and optimizing the anti-reflection(AR)optical facet coating.Compared to the Al2O3 AR coat⁃ing,the Y_(2)O_(3)A...We report on the performance improvement of long-wave infrared quantum cascade lasers(LWIR QCLs)by studying and optimizing the anti-reflection(AR)optical facet coating.Compared to the Al2O3 AR coat⁃ing,the Y_(2)O_(3)AR coating exhibits higher catastrophic optical mirror damage(COMD)level,and the optical facet coatings of both material systems have no beam steering effect.A 3-mm-long,9.5-μm-wide buried-heterostruc⁃ture(BH)LWIR QCL ofλ~8.5μm with Y_(2)O_(3)metallic high-reflection(HR)and AR of~0.2%reflectivity coating demonstrates a maximum pulsed peak power of 2.19 W at 298 K,which is 149%higher than that of the uncoated device.For continuous-wave(CW)operation,by optimizing the reflectivity of the Y_(2)O_(3)AR coating,the maximum output power reaches 0.73 W,which is 91%higher than that of the uncoated device.展开更多
In this paper,a spectral beam combining(SBC)structure of multi-single emitters laser diode based on a polarization full feedback(PFF)external cavity is proposed and demonstrated.The maximum combining efficiency is 75....In this paper,a spectral beam combining(SBC)structure of multi-single emitters laser diode based on a polarization full feedback(PFF)external cavity is proposed and demonstrated.The maximum combining efficiency is 75.6%,which leads to an output power of 38.48 W,a degree of polarization(DOP)of 99.42%,and electro-optical conversion efficiency of 35.63%under continuous wave operation at a current of 8 A.Compared to the conventional SBC,the output power,the combining efficiency,the electro-optical conversion efficiency,and the DOP of the PFF-SBC structure present improvements of 5.73 W,11.26 percentage points,5.3 percentage points,and 7.26 percentage points,respectively.The results show that this SBC method can achieve a high efficiency and linearly polarized laser output of SBC,thereby making the subsequent polarization beam-combining efficiency approach the limit.展开更多
We first study the effect of cavity modes propagating in the lateral dimension on high-power semiconductor lasers with a large stripe width.A sidewall microstructure was fabricated to prevent optical feedback of later...We first study the effect of cavity modes propagating in the lateral dimension on high-power semiconductor lasers with a large stripe width.A sidewall microstructure was fabricated to prevent optical feedback of lateral resonant modes.Theoretically,we demonstrate the existence of lateral resonant modes in the Fabry–Perot cavity with a large stripe width.Experimentally,we design the corresponding devices and compare them with conventional broad-area diode lasers.About a 15%reduction in threshold current and a 27%increase in maximum electro-optical conversion efficiency are achieved.The amplified spontaneous emission spectrum is narrowed,which proves that lateral microstructures suppress optical feedback of lateral resonant modes.Under a large continuous-wave operation,the maximum output power of laser device is43.03 W,about 1 W higher than that of the standard broad-area laser at 48 A.展开更多
In this paper,high-uniformity 2×64 silicon avalanche photodiode[APD]arrays are reported.Silicon multiple epitaxy technology was used,and the high performance APD arrays based on double-layer epiwafers are achieve...In this paper,high-uniformity 2×64 silicon avalanche photodiode[APD]arrays are reported.Silicon multiple epitaxy technology was used,and the high performance APD arrays based on double-layer epiwafers are achieved for the first time,to the best of our knowledge.A high-uniformity breakdown voltage with a fluctuation of smaller than 3.5 V is obtained for the fabricated APD arrays.The dark currents are below 90 pA for all 128 pixels at unity gain voltage.The pixels in the APD arrays show a gain factor of larger than 300 and a peak responsivity of 0.53 A/W@M=1 at 850 nm[corresponding to maximum external quantum efficiency of 81%]at room temperature.Quick optical pulse response time was measured,and a corresponding cutoff frequency up to 100 MHz was obtained.展开更多
基金Supported by the National Natural Science Foundation of China(12393830)。
文摘We report on the performance improvement of long-wave infrared quantum cascade lasers(LWIR QCLs)by studying and optimizing the anti-reflection(AR)optical facet coating.Compared to the Al2O3 AR coat⁃ing,the Y_(2)O_(3)AR coating exhibits higher catastrophic optical mirror damage(COMD)level,and the optical facet coatings of both material systems have no beam steering effect.A 3-mm-long,9.5-μm-wide buried-heterostruc⁃ture(BH)LWIR QCL ofλ~8.5μm with Y_(2)O_(3)metallic high-reflection(HR)and AR of~0.2%reflectivity coating demonstrates a maximum pulsed peak power of 2.19 W at 298 K,which is 149%higher than that of the uncoated device.For continuous-wave(CW)operation,by optimizing the reflectivity of the Y_(2)O_(3)AR coating,the maximum output power reaches 0.73 W,which is 91%higher than that of the uncoated device.
基金This work was supported by the Key Technology Research and Development Program of Shandong(Nos.2022CXGC020104 and 2023ZLYS03)the Key-Area Research and Development Program of Guangdong Province(No.2020B090922003).
文摘In this paper,a spectral beam combining(SBC)structure of multi-single emitters laser diode based on a polarization full feedback(PFF)external cavity is proposed and demonstrated.The maximum combining efficiency is 75.6%,which leads to an output power of 38.48 W,a degree of polarization(DOP)of 99.42%,and electro-optical conversion efficiency of 35.63%under continuous wave operation at a current of 8 A.Compared to the conventional SBC,the output power,the combining efficiency,the electro-optical conversion efficiency,and the DOP of the PFF-SBC structure present improvements of 5.73 W,11.26 percentage points,5.3 percentage points,and 7.26 percentage points,respectively.The results show that this SBC method can achieve a high efficiency and linearly polarized laser output of SBC,thereby making the subsequent polarization beam-combining efficiency approach the limit.
基金supported by the National Key R&D Program of China(No.2021YFA1400604)the National Natural Science Foundation of China(Nos.91850206 and 62075213)。
文摘We first study the effect of cavity modes propagating in the lateral dimension on high-power semiconductor lasers with a large stripe width.A sidewall microstructure was fabricated to prevent optical feedback of lateral resonant modes.Theoretically,we demonstrate the existence of lateral resonant modes in the Fabry–Perot cavity with a large stripe width.Experimentally,we design the corresponding devices and compare them with conventional broad-area diode lasers.About a 15%reduction in threshold current and a 27%increase in maximum electro-optical conversion efficiency are achieved.The amplified spontaneous emission spectrum is narrowed,which proves that lateral microstructures suppress optical feedback of lateral resonant modes.Under a large continuous-wave operation,the maximum output power of laser device is43.03 W,about 1 W higher than that of the standard broad-area laser at 48 A.
基金supported by the National Science and Technology Major Project(No.2018YFE0200900)。
文摘In this paper,high-uniformity 2×64 silicon avalanche photodiode[APD]arrays are reported.Silicon multiple epitaxy technology was used,and the high performance APD arrays based on double-layer epiwafers are achieved for the first time,to the best of our knowledge.A high-uniformity breakdown voltage with a fluctuation of smaller than 3.5 V is obtained for the fabricated APD arrays.The dark currents are below 90 pA for all 128 pixels at unity gain voltage.The pixels in the APD arrays show a gain factor of larger than 300 and a peak responsivity of 0.53 A/W@M=1 at 850 nm[corresponding to maximum external quantum efficiency of 81%]at room temperature.Quick optical pulse response time was measured,and a corresponding cutoff frequency up to 100 MHz was obtained.
