论文标题

用量子状态匹配的协议测试量子计算机

Testing quantum computers with the protocol of quantum state matching

论文作者

Ortega, Adrian, Kálmán, Orsolya, Kiss, Tamás

论文摘要

量子计算机中噪声的存在阻碍了它们的有效操作。即使量子误差校正可以从理论上解决此问题,但其实际实现仍然是一个挑战。因此,测试和基准测试噪声,中间量子(NISC)计算机非常重要。在这里,我们建议将所谓的量子状态匹配协议应用于测试目的。该协议最初是为了确定未知量子状​​态是否落在参考状态的规定社区中。我们分解了协议的统一特定,并构建了方案不同特征参数的动力学一步的量子电路,并针对两台不同的IBM量子计算机进行了测试结果。通过比较实验获得的成功的相对频率与理想成功概率的最大统计公差,我们将统计误差与设备特定的统计误差区分开。对于噪声的表征,我们还使用这样一个事实,即虽然理想协议的输出对输入状态的内部阶段不敏感,但实际实现可能会导致偏差。对于系统性变化的输入,我们发现具有较小量子体积的设备在我们的测试中的性能要比具有较大量子体积的设备表现更好,而对于随机输入,它们显示出更相似的性能。

The presence of noise in quantum computers hinders their effective operation. Even though quantum error correction can theoretically remedy this problem, its practical realization is still a challenge. Testing and benchmarking noisy, intermediate-scale quantum (NISC) computers is therefore of high importance. Here, we suggest the application of the so-called quantum state matching protocol for testing purposes. This protocol was originally proposed to determine if an unknown quantum state falls in a prescribed neighborhood of a reference state. We decompose the unitary specific to the protocol and construct the quantum circuit implementing one step of the dynamics for different characteristic parameters of the scheme and present test results for two different IBM quantum computers. By comparing the experimentally obtained relative frequencies of success to the ideal success probability with a maximum statistical tolerance, we discriminate statistical errors from device specific ones. For the characterization of noise, we also use the fact that while the output of the ideal protocol is insensitive to the internal phase of the input state, the actual implementation may lead to deviations. For systematically varied inputs we find that the device with the smaller quantum volume performs better on our tests than the one with larger quantum volume, while for random inputs they show a more similar performance.

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源