早在1980年代，費曼等人就已經提出用可控的量子元件來模擬量子物理的想法。如今，隨著量子技術的快速發展，各種類型的量子計算平台不斷的被實現。同時，由於隨之而來的量子技術發展，一些大規模的量子模擬，例如類比式量子模擬可藉由操控人造哈密頓量以達到模擬大規模量子材料的效果，已經可以在設計精良量子實驗平台上實現。

然而，由於受到顯著的雜訊以及設備上量子位元連接性的限制，大規模的模擬量子模擬在近代的量子電腦上往往是不可行的。因此，在這份研究中設計了一種模擬算法來解決這個問題，我們根據量子處理器的性能，自適應地將環境的影響分成小群。運用我們所提出的方法來模擬氮空缺中心的電子自旋如何在耦合到大量原子核自旋的環境下發生自由感應衰減過程，並深入探討由於核自旋極化所引起的非古典性。該模擬是在 IBMQ 上的真實系統和量子模擬器合作實現的。這項工作通過初步模擬對電路的性能進行了基準的測試，並揭示了一種在嘈雜的近期量子計算機上模擬大規模系統的靈活方法。此外，鑒於自旋-自旋相互作用，在量子計算機上模擬由核自旋環境引發的電子自旋移相動力學是特別方便的。另一方面，鑽石的氮空缺中心作為潛在有吸引力的技術，由於其電子自旋相干性對晶格中的熱震動的穩定性，使得室溫下的量子裝置有更大的機會得以實現。

The idea of simulating quantum physics with controllable quantum devices had been proposed by Feynman et al. several decades ago. Nowadays, with the accelerated growth of quantum technologies, a variety of quantum computing platforms has emerged. Meanwhile, owing to the ensuing development of quantum technologies, large-scale simulations, such as the analog quantum simulation which mimics the Hamiltonian of system of interest, have become possible to be implemented on well-designed quantum experimental platforms. Nevertheless, large-scale analog quantum simulation is often infeasible on recent quantum computers due to the limitations imposed by significant noises and the connectivity of qubits on the devices.

In this work, a simulation algorithm is designed to address this problem by adaptively dividing the effects of bath into small groups based on the performance of the quantum processor. We apply our method to simulate the electron spin free induction decay in a diamond NV− center coupling to a large number of nuclear spins and, explore the insight into the nonclassicality arising from nuclear spin polarization. The simulation is implemented collaboratively with authentic devices and quantum simulators on IBMQ. This work benchmarks circuit performance through the preliminary simulations, and reveals a flexible way to simulate largescale systems on noisy near-term quantum computers.

Furthermore, given that the spin-spin interactions, it is particularly convenient to simulate on quantum computer an electron spin dephasing dynamics triggered by a nuclear spin bath. Another aspect, towards the NV− center for diamonds stands out as potentially attractive technology, due to the robustness of its electron spin coherence against the thermal vibration in the lattice, making room temperature quantum device possible.

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