Sensing the direction of sounds gives animals clear evolutionary advantage. For large animals, with an ear-to-ear spacing that exceeds audible sound wavelengths, directional sensing is simply accomplished by recognizing the intensity and time differences of a wave impinging on its two ears¹. Recent research suggests that in smaller, subwavelength animals, angle sensing can instead rely on a coherent coupling of soundwaves between the two ears^2,3,4. Inspired by this natural design, here we show a subwarvelength photodetection pixel that can measure both the intensity and incident angle of light. It relies on an electrical isolation and optical coupling of two closely spaced Si nanowires that support optical Mie resonances^5,6,7. When these resonators scatter light into the same free-space optical modes, a non-Hermitian coupling results that affords highly sensitive angle determination. By straightforward photocurrent measurements, we can independently quantify the stored optical energy in each nanowire and relate the difference in the stored energy between the wires to the incident angle of a light wave. We exploit this effect to fabricate a subwavelength angle-sensitive pixel with angular sensitivity, δθ = 0.32°.

感知声音的方向为动物提供了明显的进化优势。对于大型动物，其耳间距离超过了可听见的声音波长，只需识别入射在其两只耳朵¹上的电波的强度和时间差，即可轻松完成定向感测。最近的研究表明，在较小的亚波长动物中，角度感应可以取而代之地依赖于两只耳朵^2,3,4之间的声波的相干耦合。受到这种自然设计的启发，我们在这里展示了可以测量光的强度和入射角的超短波长光检测像素。它依靠两个紧密间隔的硅纳米线的电隔离和光耦合，从而支持光学米氏共振^5,6,7。当这些谐振器将光散射到相同的自由空间光学模式时，会形成非赫米特耦合，从而可以确定高度敏感的角度。通过简单的光电流测量，我们可以独立地量化每条纳米线中存储的光能，并将线之间存储的能差与光波的入射角相关联。我们利用这一效果制造具有角灵敏度的亚波长角度敏感的像素，δ θ  =  0.32°。