Understanding and compensating for noise on IBM quantum computers
Understanding and compensating for noise on IBM quantum computers
复制标题
了解并补偿 IBM 量子计算机上的噪声
DOI：
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发表时间：
2021
影响因子：
0.9
通讯作者：
J. V. Van Huele
中科院分区：
文献类型：
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作者：
Scott Johnstun;J. V. Van Huele
量子算法为经典解决成本高昂的计算问题提供了有效的解决方案。公开可用的量子计算机（例如 IBM 提供的量子计算机）现在可用于运行执行量子算法的小型量子电路。然而，这些量子计算机很容易产生噪声。在这里，我们介绍了量子电路噪声和连接性的重要概念，必须解决这些概念才能在量子计算机上获得可靠的结果。我们利用几个例子来展示噪声如何随电路深度变化。我们介绍了 Simon 算法，这是一种用于解决同名计算问题的量子算法，解释了如何在 IBM Qiskit 平台中实现该算法，并比较了在无噪声模拟器和受噪声影响的物理硬件上运行该算法的结果。我们讨论了 Qiskit 转译器的影响，该转译器为量子位之间连接有限的物理硬件调整了理想的量子电路。我们证明，即使只有几个量子位的电路也会因量子噪声而显着降低其成功率，除非采取特定措施将其影响降至最低。
Quantum algorithms offer efficient solutions to computational problems that are expensive to solve classically. Publicly available quantum computers, such as those provided by IBM, can now be used to run small quantum circuits that execute quantum algorithms. However, these quantum computers are highly prone to noise. Here, we introduce important concepts of quantum circuit noise and connectivity that must be addressed to obtain reliable results on quantum computers. We utilize several examples to show how noise scales with circuit depth. We present Simon’s algorithm, a quantum algorithm for solving a computational problem of the same name, explain how to implement it in IBM’s Qiskit platform, and compare the results of running it both on a noiseless simulator and on physical hardware subject to noise. We discuss the impact of Qiskit’s transpiler, which adapts ideal quantum circuits for physical hardware with limited connectivity between qubits. We show that even circuits of only a few qubits can have their success rate significantly reduced by quantum noise unless specific measures are taken to minimize its impact.