【摘 要】
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In this work,we demonstrated high-power quantum cascade laser (QCL) arrays lasing at λ ～ 5μm by employing an op-timized coupled-ridge waveguide (CRW) structure
【机 构】
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School of Microelectronics,University of Chinese Academy of Sciences,Beijing 100049,China;Key Labora
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In this work,we demonstrated high-power quantum cascade laser (QCL) arrays lasing at λ ～ 5μm by employing an op-timized 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 diffrac-tion-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 lin-ear wavelength tuning coefficient of-0.2 cm-1/K.
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