The emergence of noisy intermediate-scale quantum (NISQ) computers has important consequences for cryptographic algorithms. It is theoretically well-established that key algorithms used in cybersecurity are vulnerable to quantum computers due to the fact that theoretical security guarantees, designed based on algorithmic complexity for classical computers, are not sufficient for quantum circuits. Many different quantum algorithms have been developed, which have potentially broad applications on future computing systems. However, this potential depends on the continued maturation of quantum hardware, which remains an area of active research and development. Theoretical limits provide an upper bound on the performance for algorithms. In practice, threats to encryption can only be accurately be assessed in the context of the rapidly evolving hardware and software landscape. Software co-design refers to the concurrent design of software and hardware as a way to understand the limitations of current capabilities and develop effective strategies to advance the state of the art. Since the capabilities for classical computation currently exceed quantum capabilities, quantum emulation techniques can play an important role in the co-design process. In this paper, we describe how the {\em cuQuantum} environment can support quantum algorithm co-design activities using widely-available commodity hardware. We describe how emulation techniques can be used to assess the impact of noise on algorithms of interest, and identify limitations associated with current hardware. We present our analysis in the context of areas of priority for cybersecurity and cryptography in particular since these algorithms are extraordinarily consequential for securing information in the digital world.

翻译：含噪中等规模量子（NISQ）计算机的出现对密码算法产生了重要影响。理论上已明确证明，由于基于经典计算机算法复杂性设计的理论安全保证对量子电路不充分，网络安全中使用的关键算法易受量子计算机攻击。目前已有多种量子算法被开发出来，这些算法对未来计算系统具有潜在广泛应用前景。然而，这一潜力取决于量子硬件的持续成熟，而该领域仍是活跃的研究与发展方向。理论极限为算法性能提供了上界约束。在实践中，对加密威胁的准确评估必须结合快速演进的硬件与软件生态系统。软硬件协同设计是指通过并行设计软件与硬件，以理解当前能力局限并制定有效策略来推进技术前沿。由于经典计算能力目前仍超过量子能力，量子仿真技术在协同设计进程中可发挥重要作用。本文描述了如何利用广泛可用的商用硬件，通过{\em cuQuantum}环境支持量子算法协同设计活动。我们阐述了如何运用仿真技术评估噪声对目标算法的影响，并识别当前硬件的局限性。鉴于密码算法对数字世界信息安全具有极其重大的影响，我们的分析将特别聚焦于网络安全和密码学领域的优先研究方向。