维格纳之友电路化：超导量子硬件上的分支间通信见证基准测试

摘要

我们在IBM量子硬件上实现并基准测试了Violaris提出的电路族，用于评估操作性的分支间通信见证量——该量定义为通过编译后的维格纳朋友式电路产生的经典测量记录中的关联性。我们以单电路内的寄存器间消息传输模式（而非物理信号传递）实现了该协议的五量子比特实例，并评估了其在真实设备噪声和编译约束下的行为。该电路编码了观察者子系统的分支条件演化，其动力学依赖于控制量子比特，随后通过受控传输操作来探测条件测量语境之间的关联性。在ibm_fez后端上执行20000次测量后，我们观测到基于布居数的可见度为0.877，沿正交轴的相干性见证量分别为0.840和-0.811，相位敏感幅度约为1.17。虽然可见度度量对某些类型的退相不敏感，但相干性见证量提供了对非对角噪声的互补敏感性。本研究并非为了检验或区分量子力学的各种诠释，而是建立了一个可复现的操作性约束流程，用于评估非理想信道相对于校准设备噪声的可检测性。

English

We implement and benchmark on IBM Quantum hardware the circuit family proposed by Violaris for estimating operational inter-branch communication witnesses, defined as correlations in classical measurement records produced by compiled Wigner's-friend-style circuits. We realize a five-qubit instance of the protocol as an inter-register message-transfer pattern within a single circuit, rather than physical signaling, and evaluate its behavior under realistic device noise and compilation constraints. The circuit encodes branch-conditioned evolution of an observer subsystem whose dynamics depend on a control qubit, followed by a controlled transfer operation that probes correlations between conditional measurement contexts. Executing on the ibm_fez backend with 20000 shots, we observe population-based visibility of 0.877, coherence witnesses of 0.840 and -0.811 along orthogonal axes, and a phase-sensitive magnitude of approximately 1.17. While the visibility metric is insensitive to some classes of dephasing, the coherence witnesses provide complementary sensitivity to off-diagonal noise. This work does not test or discriminate among interpretations of quantum mechanics. Instead, it provides a reproducible operational constraint pipeline for evaluating detectability of non-ideal channels relative to calibrated device noise.

维格纳之友电路化：超导量子硬件上的分支间通信见证基准测试

Wigner's Friend as a Circuit: Inter-Branch Communication Witness Benchmarks on Superconducting Quantum Hardware

摘要

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