Acousto-optic modulation in piezoelectric materials offers the efficient method to bridge electrical and optical signals. It is widely used to control optical frequencies and intensities in modern optical systems including Q$Q$-switch lasers, ion traps, and optical tweezers. It is also critical for emerging applications such as quantum photonics and non-reciprocal optics. Acousto-optic devices have recently been demonstrated with promising performance on integrated platforms. However, the conversion efficiency of optical signals remains low in these integrated devices. This is attributed to the significant challenge in realizing large mode overlap, long interaction length, and high power robustness at the same time. Here, we develop acousto-optic devices with gallium nitride on a sapphire substrate. The unique capability to confine both optical and acoustic fields in sub-wavelength scales without suspended structures allows efficient acousto-optic interactions over long distances under high driving power. This leads to the complete optical conversion with integrated acousto-optic modulators. With the unidirectional phase matching, we also demonstrate the non-reciprocal propagation of optical fields with isolation ratios above 10 dB. This work provides a robust and efficient acousto-optic platform, opening new opportunities for optical signal processing, quantum transduction, and non-magnetic optical isolation.

中文翻译：

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具有完整光学转换的基于集成波导的声光调制

压电材料中的声光调制提供了桥接电信号和光信号的有效方法。它广泛用于控制现代光学系统中的光学频率和强度，包括调Q$Q$激光器、离子阱和光镊。它对于量子光子学和非互易光学等新兴应用也至关重要。最近，声光器件在集成平台上被证明具有良好的性能。然而，这些集成器件中光信号的转换效率仍然很低。这是由于同时实现大模式重叠、长相互作用长度和高功率鲁棒性所面临的重大挑战。在这里，我们开发了蓝宝石衬底上氮化镓的声光器件。在没有悬挂结构的情况下将光学和声场限制在亚波长范围内的独特能力允许在高驱动功率下长距离有效的声光相互作用。这导致了集成声光调制器的完整光学转换。通过单向相位匹配，我们还演示了隔离比高于 10 dB 的光场的非互易传播。这项工作提供了一个强大而高效的声光平台，为光信号处理、量子转导和非磁光隔离开辟了新的机会。