Room-temperature continuous-wave interband cascade laser emitting at 3.45 μm<xref rid="cpb_27_12_124207fn1" ref-type="fn">*</xref><fn id="cpb_27_12_124207fn1"><label>*</label><p>Project supported by the Major Program of the National Natural Science Foundation of China (Grant No. 61790580), the National Natural Science Foundation of China (Grant No. 61435012), and the National Basic Research Program of China (Grant No. 2014CB643903).</p></fn>

Room-temperature continuous-wave interband cascade laser emitting at 3.45 μm**

Project supported by the Major Program of the National Natural Science Foundation of China (Grant No. 61790580), the National Natural Science Foundation of China (Grant No. 61435012), and the National Basic Research Program of China (Grant No. 2014CB643903).

Zhang Yi^{1, 2, 3}, Shao Fu-Hui^{1, 2, 3}, Yang Cheng-Ao^{1, 2, 3}, Xie Sheng-Wen^{1, 2, 3}, Huang Shu-Shan^{1, 2, 3}, Yuan Ye^{1, 2, 3}, Shang Jin-Ming^{1, 2, 3}, Zhang Yu^{1, 2, 3, †}, Xu Ying-Qiang^{1, 2, 3}, Ni Hai-Qiao^{1, 2, 3}, Niu Zhi-Chuan^{1, 2, 3, ‡}

The HRXRD spectrum of the 5 stages ICL ( [004] reflection). The InAs/AlSb superlattices in the picture respond to the sharp peaks. The small peaks correspond to active cascade region. And the wider peak to the right of the center peaks arises from the 20 nm-thick InAs cap layer.