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arXiv · 2409.16880

Design and experimental demonstration of photonic-crystal lasers with multijunction active layers

Shumpei Katsuno·Masahiro Yoshida·Takuya Inoue·Menaka De Zoysa·Ranko Hatsuda·Kenji Ishizaki·Susumu Noda
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Abstract

We introduce multijunction active layers, featuring a stack of alternating active layers and tunnel junctions, to PCSELs to increase their slope efficiency, which is vital for various applications including laser processing and LiDAR. First, we design a multijunction PCSEL that avoids optical absorption in the heavily-doped tunnel junctions while allowing sufficient optical gain and resonance effects in the active and photonic crystal layers. Next, we fabricate a 3-mm-diameter two-junction PCSEL, achieving a slope efficiency of 1.58 W/A, which is over twice as high as that of conventional single-junction PCSELs, and a record-high peak output power of 1.8 kW for PCSELs.

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Shumpei Katsuno, Masahiro Yoshida, Takuya Inoue, Menaka De Zoysa, Ranko Hatsuda, Kenji Ishizaki, Susumu Noda. 2024-09-25. Design and experimental demonstration of photonic-crystal lasers with multijunction active layers. https://arxiv.org/abs/2409.16880

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