Coupled-ridge waveguide quantum cascade laser array lasing at λ～5 μm

作者：Pengchang Yang; Jinchuan Zhang^*; Zenghui Gu; Chuanwei Liu; Yue Zhao; Fengmin Cheng; Shenqiang Zhai; Ning Zhuo; Junqi Liu; Lijun Wang; Shuman Liu; Fengqi Liu^*

来源：Chinese Journal of Semiconductors, 2021, 42(09): 76-80.

• quantum cascade laser array
• coupled-ridge waveguide
• mid-infrared

In this work, we demonstrated high-power quantum cascade laser(QCL) arrays lasing at λ～ 5 μm 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 2 nd-order distributed feedback(DFB) grating, substrate emission with a radiation power above 1 W at25 °C 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.

• 单位
  中国科学院大学