High-density time encoding of entangled photons for ultrafast telecom-compatible quantum secure communication

纠缠光子的高密度时间编码，用于超快电信兼容的量子安全通信

• 批准号: RTI-2021-00317
• 负责人: Morandotti, Roberto
• 金额: $ 10.93万
• 依托单位: Institut national de la recherche scientifique
• 依托单位国家: 加拿大
• 项目类别: Research Tools and Instruments
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=717995
• 关键词: density; time; encoding; entangled; photons

The rapid thrive towards supreme quantum computers puts the classical encryption techniques, used for, e.g., banking, national security, and personal online identity, at risk. Quantum cryptography offers a future-proof solution towards unbreakable security. However, low quantum key transfer rates as well as the lack of telecom-friendly, compact, and mass-producible entangled photons sources, needed for device-independent secure protocols, hamper further advances in this field. Here, we investigate multilevel (i.e., qudit) time-bin entanglement to benefit from its unique potential to boost quantum secure communication and large-capacity information processing to Gbit/s rates. Time modes are indeed widely recognized as the most accessible and robust photon degree of freedom, with significant impact on both the scientific and the industrial communities, as witnessed by the recent demonstrations of quantum encryption protocols at Mbit/s key rates over metropolitan distances. Here, by using sources of entangled photon qudits, we will demonstrate similar performances at even lower repetition rates by increasing the information capacity per photon. In this context, the requested equipment an arbitrary waveform generator (AWG) with 2 channels, analog bandwidth > 20 GHz, and timing jitter < 10 ps, as used in telecom facilities will be adapted for coherent and precise quantum state processing of densely-spaced photon time bins. We will generate and process such qudits with scalable dimensionality by using specialized on-chip optical devices, which however require operational speeds of at least few tens of picosecond for quantum state manipulation. The requested ultrafast AWG will allow us to perform multilevel time-bin projections that are critical for entanglement verification and that would be otherwise impossible to accomplish at record-fast GHz modulation-speeds. The instrument will enable us to confirm, in a short term, the first on-chip generation of time-bin entangled qudits up to 4 and even 8 levels, as well as, in a longer term, to demonstrate first-time all-fiber-integrated teleportation of 4- and 8-level photons. The accomplishment of these objectives will critically boost advances in quantum photonics, as well as will create intellectual property for Quebec and Canada towards elevating market potential for next-generation quantum technologies. Our system aims to outperform other photonic platforms in terms of 1) quantum information processing rates towards telecom-level Gbit/s, 2) enhanced information capacity per photon at higher noise robustness, and 3) increased stability, scalability, and accessibility by using chip-integrated and telecom-compatible components. The requested equipment will also greatly elevate the impact of other active projects of the PI and collaborators, as well as contribute to HQP training in highly impactful fields such as neuromorphic photonics and ultrafast signal processing.

对最高量子计算机的快速发展使经典的加密技术（例如，银行，国家安全和个人在线身份）处于危险之中。量子密码学为无法破坏的安全性提供了一个防止未来的解决方案。但是，低量子密钥传输速率以及缺乏对设备独立的安全协议所需的对电信友好，紧凑和可实现的纠缠光子源的缺乏，阻碍了该领域的进一步进步。 在这里，我们研究了多级（即Qudit）时桶纠缠，以使其从其独特的潜力中受益，以提高量子安全通信和大容量信息处理到GBIT/S速率。时间模式确实被广泛认为是最容易获得，最强大的光子自由度，对科学和工业社区都产生了重大影响，正如最近在MBIT/S关键率相比，量子加密协议的示范所见证的。在这里，通过使用纠缠的光子Qudits的来源，我们将通过增加每个光子的信息能力以较低的重复速率展示类似的性能。在这种情况下，请求的设备具有2个通道，模拟带宽> 20 GHz和定时抖动<10 ps的任意波形生成器（AWG），将适用于电信设施中的使用，以相干，精确的量子状态处理密集间隔的光子时间箱。我们将通过使用专门的片上光学设备来生成和处理具有可扩展维度的此类Qudit，但是，该设备需要至少几十秒钟的量子操作才能操作速度进行量子状态操作。请求的Ultrafast AWG将使我们能够执行对纠缠验证至关重要的多级时态预测，否则这是在记录速度fast-fast GHz调制速度上无法完成的。该仪器将使我们能够在短期内确认第一个片上的片上生成的时间键纠缠量，最多4个甚至8个级别，以及从长远来看，以展示首次全纤维全纤维的4级和8级光子的传送。这些目标的实现将严重提高量子光子学的进步，并将为魁北克和加拿大创造知识产权，以提高下一代量子技术的市场潜力。我们的系统旨在以1）量子信息处理速率以较高的噪声鲁棒性和3）使用CHIP集成和电信组成的组件提高稳定性，可及性和可访问性。所请求的设备还将大大提高PI和合作者的其他活跃项目的影响，并为高度影响力领域的HQP培训做出贡献，例如神经形态光子学和超快信号处理。