Electrically-driven silicon single-photon source

量子光源是量子信息处理、通信、传感和成像的推动者。进一步的进展需要电驱动（即电触发）的单光子源，以低损耗的电信波长发射，并且可以小型化并与硅电子电路集成。该项目旨在试验开发目前尚不具备的这种单光子源。这一奋进的成功将代表该领域前所未有的进步，并将有助于推动量子信息技术的边界，这反过来又可能导致我们在量子领域推进光学和材料科学的能力的扩展。在这样做的过程中，拟议的努力也将促进我们的工程教育和培训计划向量子技术的变革性进展，从而不仅影响博士后，毕业生的培训，该计划利用了先前在电信O波段产生明亮受激发射的突破极限的努力（~1.3 μm），由具有周期性分布的G中心（也称为碳硅“色心”）的晶体硅图案化。这个项目也将推动边界，但相反的限制-即电泵浦单光子发射，这是前所未有的硅和单色（零声子）。 通过具有纳米级孔的2D周期性阵列的Si晶体的创新纳米图案化，它将产生嵌入纳米孔侧壁中的G中心的周期性分布，该纳米孔也被机械应变和带隙降低。如我们先前的报告所示，这将允许在整体光学损耗几乎没有增加的情况下创建发射G中心，同时将注入的电荷载流子引导到G中心进行复合和发射。此外，周期性图案化将以这样的方式设计，即可以通过珀塞尔效应增强自发发射率。这将通过设计纳米孔阵列的结构和周期性来实现，以创建具有小模式体积和高密度光子状态的光子晶体，以在G中心发射的频率处/附近达到峰值。一个额外的增强可以通过用薄的势垒层阻挡漏空穴电流，同时仍然允许电子隧穿来实现。利用多孔低折射率硅层和透明电极以及光子晶体结构（纳米孔阵列）的设计，光子收集效率将被最大化，该光子晶体结构具有在横向方向上的阻带和在垂直方向上的发射锥。顶部电极也将被图案化为宏观尺寸的阵列，将允许选择性地泵浦各个SPS区，以便允许选择最亮、单色但仍满足单光子标准的单光子发射器。这些措施预计将为我们提供有史以来第一个，阵列，电泵浦，单色硅单光子源在电信O波段，兼容并准备与硅电子集成的量子信息处理。这一奖项反映了NSF的法定使命，并已被认为是值得通过评估使用基金会的智力价值和更广泛的影响审查标准的支持。

Quantum light sources are enablers of quantum information processing, communications, sensing and imaging. Further progress demands single-photon sources that are electrically-driven (i.e. electrically triggered), emit at a low-loss telecom wavelength, and can be miniaturized and integrated with silicon electronic circuits. This project aims to pilot the development of such single-photon sources that are not yet available. Success in this endeavor would represent an unprecedented advance in the field and would helppush the boundaries of quantum information technology, which in turn could lead to expansion of our capabilities in advancing optical and materials sciences in the quantum domain. In so doing, the proposed effort will also catalyze transformative advances of our engineering education and training programs towards quantum technologies, thereby not only impacting the training of postdocs, graduates, and undergraduates.The proposed effort leverages a prior limit-breaking effort in generating bright stimulated emission in the telecom O-band (~1.3 μm) from a crystalline silicon patterned with periodically distributed G-centers – also known as the carbon-silicon ‘color-center’. This project too will push the boundary, but to the opposite limit – i.e. to electrically-pumped single-photon emission, which is unprecedented in silicon and monochromatic (zero-phonon). Enabled by the innovative nanopatterning of a Si crystal with a 2D periodic array of nanoscale holes, it would create a periodic distribution of G-centers embedded in the sidewall of the nanohole which is also mechanically strained and bandgap lowered. As demonstrated in our earlier reports, this would allow one to create the emissive G-centers with little increase in the overall optical loss while simultaneously channeling the injected charge carriers to the G-centers for recombination and emission. Furthermore, the periodic patterning will be designed in such a way that the spontaneous emission rate can be enhanced via the Purcell effect. This will be achieved by engineering the structure and periodicity of the nano-hole array to create a photonic crystal with a small mode volume and a high density of photon states to peak at/near the frequency of the G-center emission. An extra enhancement can be achieved by blocking the leakage hole current with a thin barrier layer while still allowing electrons to tunnel through. The photon collection efficiency will be maximized with both the holey low-index silicon layer and the transparent electrode as well as the design of the photonic crystal structure (nanohole array) with the stop band in the lateral direction and the emission cone in the perpendicular direction. The top electrodes, also to be patterned into an array of macroscopic sizes, would allow selective pumping of individual SPS zones so as to allow selection of single-photon emitters that are brightest, monochromatic and yet still satisfy the single-photon criterion. These measures are expected to provide us the first-ever, arrayed, electrically-pumped, monochromatic silicon single-photon sources in the telecom O-band that are compatible to and ready for integration with silicon electronics for quantum information processing.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.