High orbital angular momentum lasing with tunable degree of chirality in a symmetry-broken microcavity
Zhen Qiao, Zhiyi Yuan, Song Zhu, Chaoyang Gong, Yikai Liao, Xuerui Gong, Munho Kim, Dawei Zhang, Yu‐Cheng Chen
Abstract
Chiral lasers with orbital angular momenta (OAM) are building blocks in developing high-dimensional integrated photonic devices. However, it remains demanding to arbitrarily manipulate the precise degree of chirality (DOC) and quantum numbers of OAM in microscale lasers. This study reports a strategy to generate OAM microlasers with tunable DOCs and large quantum numbers through a ring-structured Fabry–Perot microcavity with nanoscale symmetry-broken geometry. By exploiting the uneven potential of photons distributed in a microcavity, the dissymmetry factor of OAM laser can be continuously tuned from −1 to +1 by manipulating optical pump positions. High-order OAM with tunable quantum numbers were also demonstrated, in which the largest quantum number reached up to 352. Finally, multivortex laser generation on-chip in spatial and temporal domains was accomplished. This study reveals the fundamental physics of symmetry-broken cavity and provides a simple yet scalable approach for manipulating the chirality of OAM microlasers, offering insights for high-dimensional information processing and optical communications.