Co-integration of microelectronics and integrated photonics for quantum technologies

预计在未来20年内，实用量子计算机的出现将对大多数标准加密系统构成严重威胁。量子密钥分发（QKD）和量子随机数生成器（QRNG）旨在通过利用量子力学定律来增强通信和个人数据的安全性，并提供解决方案以应对恶意使用量子计算机所造成的威胁。QRNG利用量子测量的概率性质，产生真正的随机数。这与当前产生随机数的方法相反，当前的方法结合了混沌系统和基于软件的伪随机数发生器的使用，所述方法是联合收割机。QKD系统利用量子系统的特定特征，例如量子态的叠加和“不可克隆”定理，使各方能够以本质安全的方式交换加密密钥。由于QKD密钥交换是基于物理系统，而不是基于软件的加密方法，因此QKD也是“面向未来”的，因为黑客算法的改进不会影响协议的安全性。在过去的几年里，QKD和QRNG社区的努力首先集中在生产实验室原型，最近则集中在提供商业系统，这些系统已经在地球仪各地小规模部署。然而，对关键方面的关注较少，例如外形尺寸和技术可扩展性以及功耗和成本。用光纤和分立电子元件构建的系统不可避免地昂贵、笨重，并且在性能方面受到限制，因此本质上不可扩展。KETS量子安全有限公司是量子工程技术实验室（布里斯托大学）的子公司，它通过结合集成光子技术和量子密码协议的优势来解决可扩展性问题。虽然集成光子芯片显著减小了核心光学系统的尺寸，但分立电子元件和光子芯片之间的分离固有地限制了量子技术的整体性能。此外，这增加了设备的尺寸和成本，限制了这种QKD和QRNG系统的传播。 该奖学金的重点将是开发一些新的关键集成光电子系统，其中微电子和量子光子学将单片集成在同一半导体衬底上。电子学和光子学的单片集成是一个关键的技术进步，将为一系列全新的解决方案开辟道路，并将潜在地提高量子技术的性能。这可能会给QKD和QRNG系统带来突破性的改进，为它们直接集成到现代数字技术中开辟道路。

The advent of practical quantum computers, expected within the next two decades, poses a serious threat to most of standard encryption systems. Quantum Key Distribution (QKD) and Quantum Random Number Generators (QRNGs) aim to enhance security of communications and personal data by exploiting the laws of Quantum Mechanics and provide the solution to threat caused by a malicious use of quantum computers. QRNGs, exploiting the probabilistic nature of quantum measurements, produce truly random numbers. This is in opposition with current methods to generate random numbers which combine the use of chaotic systems and software-based pseudo random number generators. QKD systems taking advantage specific features of quantum systems such as superposition of quantum states and the "no-cloning" theorem enable parties to exchange cryptographic keys in an intrinsically secure way. Because QKD key exchange is based on physical systems as opposed to software-based encryption methods, QKD is also "future-proof" as no improvement on hacking algorithm will affect the security of the protocols.In the last few years, the efforts of the QKD and QRNG community have focused first to produce lab prototypes and more recently to provide commercial systems, which have been deployed in small scale around the globe. However, less focus has been placed on key aspects such as the form factor and technology scalability as well as power consumption and costs. Systems built with optical fibres and discrete electronics components are inevitably expensive, bulky, and limited in terms of performance and therefore intrinsically not scalable. KETS Quantum Security Ltd, spin-off of the Quantum Engineering Technology Labs (University of Bristol) has been addressing the scalability issues by combining the advantages of integrated photonics technologies and quantum cryptography protocols. While the integrated photonic chips have significantly reduced the size of the core optical system, separation between discrete electronic components and photonic chips inherently limits the overall performance of the quantum technology. Moreover, this increases the size of the devices and their costs, limiting the spread of this QKD and QRNG systems. The focus of this fellowship would be the development of some novel critical integrated opto-electronics systems, where microelectronics and quantum photonics will be monolithically integrated on the same semiconductor substrate. Monolithic integration of electronics and photonics is a critical technological step forward that will open the way to a whole new range of solutions and will improve the performance of quantum technologies potentially by orders of magnitude. This could bring groundbreaking improvements to QKD and QRNG systems, opening the way to their direct integration onto modern digital technologies.