Optical nonreciprocity plays a key role in almost every optical system, directing light flow and protecting optical components from backscattered light. Controllable forms of on-chip nonreciprocity are needed for the robust operation of increasingly sophisticated photonic integrated circuits (PICs) in the context of classical and quantum computation, networking, communications, and sensing. However, it has been challenging to achieve wideband, low-loss optical nonreciprocity on-chip. In this paper, we demonstrate strong coupling and Rabi-like energy exchange between photonic bands, possessing a continuum of modes, to unlock nonreciprocity and frequency translation over wide optical bandwidths in silicon. Using a traveling-wave phonon field to drive indirect interband photonic transitions, we demonstrate band hybridization that enables an intriguing form of nonreciprocal dissipation engineering. Using the converted mode to create a nonreciprocal dissipation channel, we demonstrate a frequency-neutral, low-loss (less than 1 dB) isolator with high nonreciprocal contrast (more than 14 dB) and broad operating bandwidth (more than 59 GHz). Additionally, through the implementation of complete interband conversion, we demonstrate a high extinction (more than 55 dB) optical frequency translation operation with near-unity efficiency.

中文翻译：

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通过连续模式的强耦合进行不可逆耗散工程

光学非互易性在几乎每个光学系统中都起着关键作用，它可以引导光流并保护光学元件免受反向散射光的影响。在经典和量子计算、网络、通信和传感领域，日益复杂的光子集成电路 (PIC) 的稳健运行需要可控形式的片上非互易性。然而，在片上实现宽带、低损耗光学非互易性一直具有挑战性。在本文中，我们展示了光子带之间的强耦合和类拉比能量交换，具有连续的模式，以解锁硅中宽光学带宽上的非互易性和频率转换。使用行波声子场驱动间接带间光子跃迁，我们演示了能带杂化，它能够实现一种有趣的非互易耗散工程形式。使用转换模式创建不可逆耗散通道，我们演示了一种频率中性、低损耗（小于 1 dB）隔离器，具有高不可逆对比度（超过 14 dB）和宽工作带宽（超过 59 GHz）。此外，通过实现完整的带间转换，我们展示了具有接近统一效率的高消光（超过 55 dB）光学频率转换操作。