On-chip platforms for engineering photon-photon interactions and low-power photonic devices

这项研究的目的是开发高度增强光-物质相互作用的芯片平台，进而可以用来设计单光子或少光子光脉冲之间的非线性相互作用。尽管在与单个光子相关的功率下，基于光的信息处理所需的非线性光-物质相互作用在传统材料中变得几乎可以忽略不计，但单个光子之间的相互作用可以通过所谓的“量子发射体”中产生的光学非线性来实现。根据这一提议开发的平台将使用这种基于量子发射器的非线性，并通过使用半导体制造技术制造的光子纳米结构来增强它们。由此产生的系统将具有较小的物理占地面积，将很容易与集成电路接口，并将被用于低功率信息处理的新型光子器件，作为可扩展量子信息处理应用的构建块，以及在凝聚态或原子系统中的量子力学现象的研究。*拟议的研究将通过追求以下两个相互关联的主题来实现其目标：*1)带有包含量子发射体介观系综的片上波导的非线性量子光学：*量子发射体系综可以在实现单光子非线性方面提供显著的优势。这些优势包括光-物质相互作用的集体增强，对噪声和消相干的稳健性，以及处理包含多个光子的脉冲的能力。这项拟议的研究将探索限制在片上空心波导中的激光冷却原子的量子光学，用于光学晶体管和存储器、量子非破坏性单光子探测器和超稳定激光器。*2)将单个激光冷却的原子耦合到平面光子晶体纳米腔阵列的非线性量子光学：由于光子晶体腔的体积非常小，将激光冷却的原子耦合到这些腔中可以得到一种能够在不受原子自然线宽(~MHz)限制的大带宽(~GHz)上运行的器件。这样的性能将可与基于耦合到固态量子发射器的腔的电流原理验证设备相媲美。然而，由于与固态量子发射器不同，所有的原子本质上都是相同的，根据这一建议开发的这种混合原子-腔体器件可以扩展到多器件片上架构，用于接近基本功率限制的经典信息处理，以及用于量子信息处理、量子传感和量子模拟。*在拟议的研究期间，总共将有四名博士生接受光子学和量子技术领域的培训。**

The intent of the proposed research is to develop on-chip platforms in which light-matter interactions are highly enhanced, which in turn can be used to engineer nonlinear interactions between single-photon or few-photon light pulses. While nonlinear light-matter interactions needed for light-based information processing become close to negligible in conventional materials at powers associated with individual photons, interactions between single photons can be achieved through optical non-linearities arising in so-called "quantum emitters". The platforms developed under this proposal will use such quantum-emitter based nonlinearities and enhance them with photonic nanostructures fabricated using semiconductor manufacturing techniques. The resulting systems will have small physical footprint, will easily interface with integrated electronic circuits, and will be utilized toward novel photonic devices for low-power information processing, as building blocks for scalable quantum information processing applications, as well as in studies of quantum-mechanical phenomena in condensed matter or atomic systems.***The proposed research will achieve its goals by pursuing the following two interrelated themes: ***1) Nonlinear quantum optics with on-chip waveguides containing mesoscopic ensembles of quantum emitters:***Ensembles of quantum emitters can offer significant advantages in implementing single-photon nonlinearities. These advantages include collective enhancement of light-matter interactions, robustness to noise and decoherence, and the ability to handle pulses containing multiple photons. The proposed research will explore quantum optics with ensembles of laser-cooled atoms confined inside on-chip hollow waveguides for applications such as optical transistors and memories, quantum non-demolition single-photon detectors, and ultra-stable lasers. ***2) Nonlinear quantum optics with individual laser-cooled atoms coupled to arrays of planar photonic-crystal nano-cavities : ***Because of the extremely small volume of photonic-crystal cavities, coupling laser-cooled atoms to these cavities can lead to a device capable of performing over a large bandwidth (~GHz) not limited by the natural linewidth (~MHz) of the atoms. Such performance will be comparable to current proof-of-principle devices based on cavities coupled to solid-state quantum emitters. However, since all the atoms are inherently identical unlike solid-state quantum emitters, such hybrid atom-cavity devices developed under this proposal can be scaled into multi-device on-chip architectures for classical information processing near fundamental power limits, as well as for quantum information processing, quantum sensing, and quantum simulations.*** Four doctoral students in total will be trained in the areas of photonics and quantum technologies during the period of the proposed research.**