论文标题
在计算假设下对单个量子设备进行自我测试
Self-testing of a single quantum device under computational assumptions
论文作者
论文摘要
自我测试是一种仅基于其经典输入相关性来表征任意量子系统的方法，并在独立于设备的量子信息处理以及量子复杂性理论中起重要作用。自我测试的先前工作需要假设系统的状态在多个只执行本地测量且无法交流的各方共享。在这里，我们替换了由单个计算方面的一方在实践中难以执行的多个非交流方的设置。具体而言，我们构建了一个协议，该协议允许经典的验证器鲁棒证明单个计算界限的量子设备必须已经准备了铃铛对并在其上进行了单量测量，直到更改了应用于设备状态和测量值的基础。这意味着，在计算假设下，验证者能够证明纠缠的存在，纠缠是在一个量子设备内，通常与两个分离的子系统密切相关的属性。为了实现这一目标，我们基于Brakerski等人首先引入的技术。 （2018）和Mahadev（2018），允许经典验证器限制假设该设备不会破坏量子后加密的量子设备的动作。
Self-testing is a method to characterise an arbitrary quantum system based only on its classical input-output correlations, and plays an important role in device-independent quantum information processing as well as quantum complexity theory. Prior works on self-testing require the assumption that the system's state is shared among multiple parties that only perform local measurements and cannot communicate. Here, we replace the setting of multiple non-communicating parties, which is difficult to enforce in practice, by a single computationally bounded party. Specifically, we construct a protocol that allows a classical verifier to robustly certify that a single computationally bounded quantum device must have prepared a Bell pair and performed single-qubit measurements on it, up to a change of basis applied to both the device's state and measurements. This means that under computational assumptions, the verifier is able to certify the presence of entanglement, a property usually closely associated with two separated subsystems, inside a single quantum device. To achieve this, we build on techniques first introduced by Brakerski et al. (2018) and Mahadev (2018) which allow a classical verifier to constrain the actions of a quantum device assuming the device does not break post-quantum cryptography.
