[TuD1] Advanced Semiconductor Lasers (II)

8:30 AM - 9:00 AM JST(11:30 PM - 12:00 AM UTC)

[TuD1-01 Invited] From Wafer-Scale VCSEL Arrays to Fusion-Class Output:
A Photonic-Band Design Framework for Coherent Array Scaling

〇Tatsushi Hamaguchi¹, Haisong Jiang¹, Miki Isoda¹, Kiichi Hamamoto¹ (1. Kyushu University (Japan))

VCSEL arrays offer a promising path to power scaling beyond conventional “high-power” semiconductor lasers because they can expand in two dimensions, enabling output to grow with aperture area rather than only linearly with width. However, the key barrier is maintaining spatial coherence and beam quality as the array size increases: without phase control, large arrays emit with LED-like coherence. This invited talk discusses recent indications of emergent phase synchronization in laterally structured VCSEL systems and introduces a photonic-band–inspired design framework for coherent 2D scaling. By treating phase coherence as a primary design target, the framework provides a systematic way to select cavity and array geometries, identify stable collective modes, and guide engineering trade-offs among thermal management, current injection locality, and far-field beam quality. The presentation outlines the conceptual basis of the approach, practical implications for wafer-scale architectures, and a roadmap toward ultra-high-power operation with useful brightness, highlighting how band-theoretic thinking can unify modeling and design for next-generation coherent VCSEL arrays.