Electrically-driven silicon single-photon source

量子光源是量子信息处理、通信、传感和成像的使能器。未来的发展要求单光子光源是电驱动的(即电触发的)，发射在低损耗的电信波长，并且可以小型化并与硅电子电路集成。该项目旨在试行目前尚不存在的单光子源的开发。这一努力的成功将代表着该领域的前所未有的进步，并将帮助打破量子信息技术的边界，这反过来可能导致我们在量子领域推动光学和材料科学的能力的扩展。通过这样做，拟议的努力还将催化我们的工程教育和培训计划对量子技术的变革性进展，从而不仅影响博士后、研究生和本科生的培养。拟议的努力利用先前的突破限制的努力，在电信O波段(~1.3μm)从周期性分布的G中心的晶体硅图案中产生明亮的受激辐射-也被称为碳-硅‘色心’。这个项目也将把这一界限推向相反的极限--即电泵浦的单光子发射，这在硅和单色(零声子)领域是前所未有的。利用具有2D周期性纳米孔阵列的创新纳米硅晶体，它将产生嵌入在纳米孔侧壁的G中心的周期性分布，这也是机械应变和带隙降低的结果。正如我们早先的报告中所展示的，这将允许人们在几乎不增加总体光学损失的情况下创建发射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，周期性图案的设计将通过珀塞尔效应来提高自发发射率。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的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止漏穴电流，同时仍然允许电子通过隧道来实现。低折射率多孔硅层和透明电极以及横向带有阻挡带、垂直方向有发射锥体的光子晶体结构(纳米孔阵列)的设计将使光子收集效率最大化。顶部电极也将被图案化成宏观尺寸的阵列，将允许选择性地抽运单个SPS区，从而允许选择最亮、单色且仍满足单光子标准的单光子发射体。这些措施有望为我们提供电信O波段中第一个阵列的、电抽运的单色硅单光子源，这些源与用于量子信息处理的硅电子学兼容并准备与其集成。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

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.