Since their first observation in metallic alloys, quasicrystals have remained highly intriguing ubiquitous physical structures, sharing properties of ordered and disordered media. They can be created in various ways, including optically induced or technologically fabricated structures in photonic and phononic systems. Understanding the wave propagation in such two-dimensional structures attracts considerable attention, with strikingly different localization properties observed in various quasicrystalline systems. Direct observation of localization in purely linear photonic quasicrystals remains elusive, and the impact of varying rotational symmetry on localization is yet to be understood. Here, using sets of interfering plane waves, we create photonic two-dimensional quasicrystals with different rotational symmetries. We demonstrate experimentally that linear localization of light does occur even in clean linear quasicrystals. We found that light localization occurs above a critical depth of optically induced potential and that this critical depth rapidly decreases with increasing order of the discrete rotational symmetry of the quasicrystal. These findings pave the way for achieving wave localization in a wide variety of aperiodic systems obeying discrete symmetries, with possible applications in photonics, atomic physics, acoustics and condensed matter.

自从首次在金属合金中观察到准晶体以来，准晶体一直是非常有趣的普遍物理结构，具有有序和无序介质的共同特性。它们可以通过多种方式创建，包括光子和声子系统中的光诱导或技术制造的结构。了解这种二维结构中的波传播引起了相当多的关注，在各种准晶系统中观察到了截然不同的局域特性。直接观察纯线性光子准晶体中的局域化仍然难以捉摸，并且不同的旋转对称性对局域化的影响还有待了解。在这里，我们使用一组干涉平面波，创建了具有不同旋转对称性的光子二维准晶体。我们通过实验证明，即使在干净的线性准晶体中也确实会发生光的线性局域化。我们发现光局域化发生在光感应势的临界深度之上，并且该临界深度随着准晶体离散旋转对称性阶数的增加而迅速减小。这些发现为在遵守离散对称性的各种非周期系统中实现波局域化铺平了道路，并可能在光子学、原子物理、声学和凝聚态物质中得到应用。