Integrated Photonic Chips for Generating Entangled Photon Triplets

量子信息技术是基础物理学进步的驱动力，能够实现大规模安全通信、前所未有的处理器速度和更高分辨率的测量技术。这些应用需要一个纠缠光子的源，它作为具有有趣量子特性的信息位，以及可以操纵和测量这些光子的电路。一种几乎未被探索的方法是在一个步骤中产生三个纠缠光子。这一方案大大简化了更大纠缠态的产生，使得令人兴奋的量子实验成为可能，并填补了量子计算机发展的巨大空白。在这个项目中，研究人员和他的学生将使用二氧化钛（TiO 2）集成光子电路，以一种强大的，可扩展的和商业上可行的形式产生三胞胎。利用他们在TiO 2、非线性光学和集成光子器件方面的专业知识，该小组将开发一种在电信波长下直接产生纠缠三重态光子的光源。TiO 2和光子集成量子电路的成熟将推动量子信息科学领域朝着可商业化产品的方向发展。在推进上述领域的发现的同时，该项目还将通过本科生和研究生的研究型教育，为培养未来的多学科科学家和工程师做出贡献。量子信息技术是基础理论进步的驱动力，可以实现大规模安全网络，量子信息处理器以及增强的测量和光刻技术。光子学是此类技术的理想平台;然而，单个和纠缠光子的产生、操纵和检测仍然是一个挑战。虽然自发的单光子和成对光子的来源很普遍，但三重态光子源几乎完全未被探索，代表了量子理论中基本测试的缺失环节，并预示着量子通信和计算的光子对。此外，三重态光子源显著简化了更大纠缠态的产生。该项目将寻求开发一种可以直接产生电信波长的纠缠三重态光子的源（例如，1500 nm）以4，000个三重峰/秒的速率（比目前的实验努力大六个数量级）使用三阶自发参数下转换。通过耦合到谐振腔，该组将进一步提高发射率的一个额外的数量级，并改善光谱控制。TiO 2是这一过程的理想材料，因为它的高透明度，大的非线性，高线性折射率，和可忽略的荧光。该小组将利用TiO 2器件中强大的、持续的非线性和严格的光限制，直接在芯片上实现前所未有的三重态光子产生速率，在芯片上可以很容易地路由、操纵，然后使用集成探测器进行测量。

Quantum information technologies are a driving force for the advancement of fundamental physics and enable large-scale secure communication, unprecedented processor speeds, and higher resolution measurement techniques. These applications require a source of entangled photons, which act as bits of information with interesting quantum properties, as well as circuits that can manipulate and measure these photons. An almost unexplored approach is to generate triplets of entangled photons in a single step. This scheme significantly simplifies the generation of larger entangled states, enabling exciting quantum experiments and filling a huge gap in the development of quantum computers. In this project, the investigator and his students will use titanium dioxide (TiO2) integrated photonic circuits to produce triplets in a robust, scalable, and commercially viable format. Leveraging their expertise in TiO2, nonlinear optics and integrated photonic devices, the group will develop a source that directly produces entangled triplet photons at telecommunications wavelengths. Maturation of TiO2 and photonic integrated quantum circuits will move the field of quantum information science in the direction of commercializable products. While advancing the discoveries in the fields described above, this project will also contribute to the training of future multidisciplinary scientists and engineers through research-based education of undergraduate and graduate students. Quantum information technologies are a driving force for the advancement of fundamental theories and can enable large-scale secure networks, quantum information processors, and enhanced measurement and lithographic techniques. Photonics is an ideal platform for such technologies; however, the generation, manipulation, and detection of single and entangled photons remain a challenge. While sources of spontaneous single and pairs of photons are widespread, triplet-photon sources are almost completely unexplored and represent the missing link for fundamental tests in quantum theory and heralded photon pairs for quantum communication and computation. Furthermore, a triplet-photon source significantly simplifies the generation of larger entangled states. This project will seek to developm a source that can directly produce entangled triplet photons at telecommunications wavelengths (e.g., 1500 nm) at a rate of 4,000 triplets/sec (six orders of magnitude greater than current experimental efforts) using third-order spontaneous parametric down-conversion. By coupling to a resonant cavity, the group will further enhance the emission rate by an additional order of magnitude and improve spectral control. TiO2 is the ideal material for this process because of its high transparency, large nonlinearity, high linear refractive indices, and negligible fluorescence. The group will exploit the strong, sustained nonlinearity and tight light-confinement in TiO2 devices to achieve unprecedented triplet-photon generation rates directly on chip, where they can readily be routed, manipulated, and then measured using integrated detectors.