We introduce a wavelength-addressable diffractive optical network that transforms illumination wavelength into a high-dimensional control parameter for arbitrarily programmable 2D beam steering. The proposed passive architecture comprises cascaded spatially optimized diffractive layers, jointly designed using deep learning, to rapidly map distinct wavelengths to predefined/desired output angles. Unlike conventional single-layer dispersive optical elements, which are physically restricted to 1D linear mapping, this framework harnesses complex wavefront transformations to utilize the illumination wavelength as an intrinsic addressing key for arbitrary 2D beam steering, eliminating the need for mechanical scanning or electronic phase control. We numerically demonstrate wavelength-controlled beam steering across 625 wavelength channels spanning 400-750 nm, realizing a 25 x 25 array of independently addressable beam positions with subwavelength positioning accuracy and high channel fidelity. Unlike conventional gratings, which constrain wavelength routing to a linear trajectory, the proposed diffractive network performs nonlocal wavefront transformations, enabling arbitrary wavelength-to-angle mappings across a 2D field of view. We further validate the proposed framework experimentally in both the terahertz and visible spectral regimes, demonstrating wavelength-multiplexed beam steering using 3D fabricated passive diffractive layers at terahertz frequencies and phase-only spatial light modulators in the visible spectrum. This wavelength-addressable diffractive architecture establishes a compact and scalable paradigm for high-speed programmable beam steering, with potential applications in optical communications, routing, imaging, sensing, and emerging photonic information-processing systems.

翻译：我们提出一种波长可寻址的衍射光学网络，该网络将照明波长转化为高维控制参量，实现任意可编程的二维波束操控。所提无源架构由级联空间优化衍射层构成，通过深度学习联合设计，可快速将不同波长映射至预定义/期望输出角度。与局限于一维线性映射的传统单层色散光学元件不同，该框架利用复杂波前变换将照明波长作为内禀寻址密钥，实现任意二维波束操控，无需机械扫描或电子相位控制。我们在涵盖400-750 nm波段的625个波长通道上数值演示了波长控制的波束操控，实现了25×25阵列的独立可寻址波束位置，具有亚波长定位精度和高通道保真度。与将波长路由约束为线性轨迹的传统光栅不同，所提衍射网络执行非局部波前变换，可在二维视场内实现任意波长-角度映射。我们进一步在太赫兹和可见光谱波段通过实验验证了该框架：在太赫兹频段使用3D制备的无源衍射层，在可见光谱段使用纯相位空间光调制器，分别实现了波长复用的波束操控。该波长可寻址衍射架构为高速可编程波束操控建立了紧凑且可扩展的范式，可应用于光通信、路由、成像、传感及新兴光子信息处理系统。