量子糾纏是極為重要的量子關聯性，在量子通訊、量子資訊、量子加密等領域具有關鍵應用。然而，驗證量子糾纏，特別是系統與環境之間的糾纏，仍是一項具有挑戰性的問題。其原因在於環境通常包含龐大的自由度，難以直接觀測與描述。近期研究指出，哈密頓量系綜表示（Hamiltonian ensemble representation）能夠用來驗證純退相干動力學（pure dephasing dynamics）中產生的系統環境量子關聯。然而，該方法主要是驗證量子不和諧度（quantum discord），尚無法直接判定量子糾纏；此外，其實驗實作需要重建各時間點的量子演化過程，增加了實驗上的困難度。為了解決上述問題，我們提出了一套基於混合么正通道（mixed unitary channel）概念的新理論，以驗證系統環境間的量子關聯性。我們進一步證明，在純退相干過程中產生的量子不和諧度等價於量子糾纏。因此我們得出以下結論：在純退相干過程中，若系統無法以混合么正通道描述，則系統必定會與環境產生量子糾纏。最後，我們利用雲端量子電腦上模擬退相干量子動力學來證實此方法的可行性，並進一步比較其與哈密頓量系綜方法在分析能力與實驗實作上的優缺點。

Quantum entanglement is a fundamental quantum correlation with crucial applications in quantum communication, quantum information, and quantum cryptography. However, verifying quantum entanglement, especially system-environment entanglement, remains a highly challenging task because the environment typically contains a large number of degrees of freedom that are difficult to access and characterize directly. Recent studies have shown that Hamiltonian ensemble representation of quantum dynamics can be used to verify system-environment quantum correlations generated during pure dephasing processes. Nevertheless, this approach is mainly limited to detecting quantum discord and cannot directly identify quantum entanglement. Moreover, its experimental implementation requires the reconstruction of the quantum evolution at each time step, which could lead to experimental overhead. To address these challenges, we propose a new theoretical framework based on mixed unitary channels to verify system-environment quantum correlations. Notably, we prove that, for pure dephasing processes, the emergence of quantum discord also implies the generation of quantum entanglement. As a result, we obtain the following conclusion: if the system dynamics in a pure dephasing process cannot be described by a mixed unitary channel, then the system must become entangled with the environment. Finally, we demonstrate the feasibility of this approach by simulating pure dephasing quantum dynamics on a cloud quantum computer, and we further compare its analytical capabilities and experimental practicality with those of the Hamiltonian ensemble approach.

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