The combination of electrophysiology and optogenetics enables the exploration of how the brain operates down to a single neuron and its network activity. Neural probes are in vivo invasive devices that integrate sensors and stimulation sites to record and manipulate neuronal activity with high spatiotemporal resolution. State-of-the-art probes are limited by tradeoffs involving their lateral dimension, number of sensors, and ability to access independent stimulation sites. Here, we realize a highly scalable probe that features three-dimensional integration of small-footprint arrays of sensors and nanophotonic circuits to scale the density of sensors per cross-section by one order of magnitude with respect to state-of-the-art devices. For the first time, we overcome the spatial limit of the nanophotonic circuit by coupling only one waveguide to numerous optical ring resonators as passive nanophotonic switches. With this strategy, we achieve accurate on-demand light localization while avoiding spatially demanding bundles of waveguides and demonstrate the feasibility with a proof-of-concept device and its scalability towards high-resolution and low-damage neural optoelectrodes.

电生理学和光遗传学的结合可以探索大脑如何运作到单个神经元及其网络活动。神经探针是体内侵入式设备，它集成了传感器和刺激位点，以高时空分辨率记录和操纵神经元活动。最先进的探头受到涉及横向尺寸、传感器数量和访问独立刺激部位的能力的权衡的限制。在这里，我们实现了一种高度可扩展的探针，它具有传感器和纳米光子电路的小尺寸阵列的三维集成，以相对于最先进的设备将每个横截面的传感器密度扩展一个数量级. 首次，我们通过仅将一个波导耦合到许多光学环形谐振器作为无源纳米光子开关来克服纳米光子电路的空间限制。通过这种策略，我们实现了精确的按需光定位，同时避免了空间要求高的波导束，并证明了概念验证设备的可行性及其向高分辨率和低损伤神经光电电极的可扩展性。