Xu Mingyu, Lei Peng, Bai Yunhui, Chen Zhangyuan, Xie Xiaopeng
Opt Lett. 2024 Aug 15;49(16):4541-4544. doi: 10.1364/OL.533979.
Stimulated Brillouin scattering (SBS) is a nonlinear optical phenomenon mediated from the coupling of photons and phonons. It has found applications in various realms, yet the acousto-optic interaction strength remains relatively weak. Enhancing the SBS with resonant structures could be a promising solution, but this method faces strict constraints in operational bandwidth. Here, we present the first demonstration to our knowledge of the broadband enhancement of Brillouin nonlinearities by a suspended coupled resonator optical waveguide (CROW) on an SOI platform. By comprehensively balancing the Brillouin gain and operational bandwidth, a 3-fold enhancement for the Brillouin gain coefficient (G) and a broad operational bandwidth of over 80 GHz have been achieved. Furthermore, this 1.1 mm device shows a forward Brillouin gain coefficient of 2422 mW and a high mechanical quality factor (Q) of 1060. This approach marks a pivotal advancement toward wide bandwidth, low energy consumption, and compact integrated nonlinear photonic devices, with potential applications in tunable microwave photonic filters and phonon-based non-reciprocal devices.
受激布里渊散射（SBS）是一种由光子与声子耦合介导的非线性光学现象。它已在各个领域得到应用，但其声光相互作用强度仍然相对较弱。利用谐振结构增强SBS可能是一种很有前景的解决方案，但这种方法在工作带宽方面面临严格限制。在此，据我们所知，我们首次展示了在硅基绝缘体上硅（SOI）平台上通过悬浮耦合谐振器光波导（CROW）实现布里渊非线性的宽带增强。通过全面平衡布里渊增益和工作带宽，实现了布里渊增益系数（G）提高3倍以及超过80 GHz的宽工作带宽。此外，这个1.1毫米的器件显示出2422 mW的前向布里渊增益系数和1060的高机械品质因数（Q）。这种方法标志着朝着宽带宽、低能耗和紧凑型集成非线性光子器件迈出了关键的一步，在可调谐微波光子滤波器和基于声子的非互易器件中具有潜在应用。
