In this work,we demonstrated high-power quantum cascade laser(QCL)arrays lasing at λ~5μm by employing an optimized coupled-ridge waveguide(CRW)structure.Five-element QCL arrays were simulated and fabricated through ...In this work,we demonstrated high-power quantum cascade laser(QCL)arrays lasing at λ~5μm by employing an optimized coupled-ridge waveguide(CRW)structure.Five-element QCL arrays were simulated and fabricated through a two-step etching method to extend the CRW structure to a mid-wave infrared regime.A lateral far-field with the main peak near a diffraction-limited intensity curve of about 10°was observed by properly designing a geometric shape of the ridges and interspaces.By introducing a buried 2nd-order distributed feedback(DFB)grating,substrate emission with a radiation power above 1 W at 25℃ is achieved.Single longitudinal mode operation is obtained by changing the temperature of the heatsink with a good linear wavelength tuning coefficient of -0.2 cm^(-1)/K.展开更多
To facilitate the development of on-chip integrated mid-infrared multi-channel gas sensing systems,we propose a high-power dual-mode(7.01 and 7.5μm)distributed feedback quantum cascade laser based on stacked 3D monol...To facilitate the development of on-chip integrated mid-infrared multi-channel gas sensing systems,we propose a high-power dual-mode(7.01 and 7.5μm)distributed feedback quantum cascade laser based on stacked 3D monolithic integration.Longitudinal mode control is achieved by preparing longitudinal nested bi-periodic compound one-dimensional Bragg gratings along the direction of the cavity length in the confinement layer.Additionally,transverse coherent coupling ridges perpendicular to the cavity length direction are fabricated in the upper waveguide layer to promote the fundamental transverse mode output when all ridges are in phase.Stable dual-wavelength simultaneous emission with a side-mode suppression ratio of more than 20 dB was achieved by holographic exposure and wet etching.The entire spectral tuning range covers nearly 100 nm through joint tuning of the injection current and heat-sink temperature.High peak power and beam quality are guaranteed by the parallel coherent integration of seven-element ridge arrays.The device operates in a fundamental supermode with a single-lobed far-field pattern,and its peak output power reaches 3.36 W in pulsed mode at 20℃.This dual-mode laser chip has the potential for in-situ on-chip simultaneous detection of CH4and C2H6gases in leak monitoring.展开更多
基金supported by National Basic Research Program of China(Grant Nos.2018YFA0209103,2018YFB2200504)in part by National Natural Science Foundation of China(Grant Nos.61991430,61774146,61790583,61734006,61835011,61674144,61774150,61805168)+1 种基金in part by Beijing Municipal Science&Technology Commission(Grant No.Z201100004020006)in part by the Key projects of the Chinese Academy of Sciences(Grant No.2018147,Grant No.YJKYYQ20190002,Grant No.QYZDJ-SSW-JSC027,Grant No.XDB43000000,Grant No.ZDKYYQ20200006).
文摘In this work,we demonstrated high-power quantum cascade laser(QCL)arrays lasing at λ~5μm by employing an optimized coupled-ridge waveguide(CRW)structure.Five-element QCL arrays were simulated and fabricated through a two-step etching method to extend the CRW structure to a mid-wave infrared regime.A lateral far-field with the main peak near a diffraction-limited intensity curve of about 10°was observed by properly designing a geometric shape of the ridges and interspaces.By introducing a buried 2nd-order distributed feedback(DFB)grating,substrate emission with a radiation power above 1 W at 25℃ is achieved.Single longitudinal mode operation is obtained by changing the temperature of the heatsink with a good linear wavelength tuning coefficient of -0.2 cm^(-1)/K.
基金National Key Research and Development Program of China(2021YFB3201901)National Natural Science Foundation of China(61835011,61991430,62335015)Key Program of the Chinese Academy of Sciences(XDB43000000)。
文摘To facilitate the development of on-chip integrated mid-infrared multi-channel gas sensing systems,we propose a high-power dual-mode(7.01 and 7.5μm)distributed feedback quantum cascade laser based on stacked 3D monolithic integration.Longitudinal mode control is achieved by preparing longitudinal nested bi-periodic compound one-dimensional Bragg gratings along the direction of the cavity length in the confinement layer.Additionally,transverse coherent coupling ridges perpendicular to the cavity length direction are fabricated in the upper waveguide layer to promote the fundamental transverse mode output when all ridges are in phase.Stable dual-wavelength simultaneous emission with a side-mode suppression ratio of more than 20 dB was achieved by holographic exposure and wet etching.The entire spectral tuning range covers nearly 100 nm through joint tuning of the injection current and heat-sink temperature.High peak power and beam quality are guaranteed by the parallel coherent integration of seven-element ridge arrays.The device operates in a fundamental supermode with a single-lobed far-field pattern,and its peak output power reaches 3.36 W in pulsed mode at 20℃.This dual-mode laser chip has the potential for in-situ on-chip simultaneous detection of CH4and C2H6gases in leak monitoring.
