论文标题

准确计算量子环的电子特性

Accurately computing electronic properties of a quantum ring

论文作者

Neill, C., McCourt, T., Mi, X., Jiang, Z., Niu, M. Y., Mruczkiewicz, W., Aleiner, I., Arute, F., Arya, K., Atalaya, J., Babbush, R., Bardin, J. C., Barends, R., Bengtsson, A., Bourassa, A., Broughton, M., Buckley, B. B., Buell, D. A., Burkett, B., Bushnell, N., Campero, J., Chen, Z., Chiaro, B., Collins, R., Courtney, W., Demura, S., Derk, A. R., Dunsworth, A., Eppens, D., Erickson, C., Farhi, E., Fowler, A. G., Foxen, B., Gidney, C., Giustina, M., Gross, J. A., Harrigan, M. P., Harrington, S. D., Hilton, J., Ho, A., Hong, S., Huang, T., Huggins, W. J., Isakov, S. V., Jacob-Mitos, M., Jeffrey, E., Jones, C., Kafri, D., Kechedzhi, K., Kelly, J., Kim, S., Klimov, P. V., Korotkov, A. N., Kostritsa, F., Landhuis, D., Laptev, P., Lucero, E., Martin, O., McClean, J. R., McEwen, M., Megrant, A., Miao, K. C., Mohseni, M., Mutus, J., Naaman, O., Neeley, M., Newman, M., O'Brien, T. E., Opremcak, A., Ostby, E., Pato, B., Petukhov, A., Quintana, C., Redd, N., Rubin, N. C., Sank, D., Satzinger, K. J., Shvarts, V., Strain, D., Szalay, M., Trevithick, M. D., Villalonga, B., White, T. C., Yao, Z., Yeh, P., Zalcman, A., Neven, H., Boixo, S., Ioffe, L. B., Roushan, P., Chen, Y., Smelyanskiy, V.

论文摘要

一种有前途的研究凝结物系统的方法是在工程量子平台上模拟它们。但是,实现胜过经典方法所需的准确性是一个重大的挑战。在这里,使用十八个超导量子台,我们为精确的冷凝 - 含量模拟器提供了实验性蓝图,并演示了如何探测基本电子性能。我们通过重建一维电线的单粒子带结构来基于基础方法。我们证明了几乎完全缓解了破坏性和读数误差,并得出了测量该线的能量特征值的准确性,误差为〜0.01 rad,而典型的能量尺度为1 rad。通过突出傅立叶变换的鲁棒性能,包括解决以1E-4 rad的统计不确定性解决特征力的能力,可以洞悉这种前所未有的算法保真度。此外,我们合成磁通量和无序的局部电位,这是一个凝结物系统的两个关键原则。当扫描磁通量时,我们观察到频谱中避免了水平的交叉,这是局部疾病空间分布的详细指纹。结合了这些方法,我们重建了本征态的电子特性,我们观察到持续的电流和对添加障碍的电导强烈抑制。我们的工作描述了一种准确的量子模拟方法,并铺平了用超导码头研究新型量子材料的方式。

A promising approach to study condensed-matter systems is to simulate them on an engineered quantum platform. However, achieving the accuracy needed to outperform classical methods has been an outstanding challenge. Here, using eighteen superconducting qubits, we provide an experimental blueprint for an accurate condensed-matter simulator and demonstrate how to probe fundamental electronic properties. We benchmark the underlying method by reconstructing the single-particle band-structure of a one-dimensional wire. We demonstrate nearly complete mitigation of decoherence and readout errors and arrive at an accuracy in measuring energy eigenvalues of this wire with an error of ~0.01 rad, whereas typical energy scales are of order 1 rad. Insight into this unprecedented algorithm fidelity is gained by highlighting robust properties of a Fourier transform, including the ability to resolve eigenenergies with a statistical uncertainty of 1e-4 rad. Furthermore, we synthesize magnetic flux and disordered local potentials, two key tenets of a condensed-matter system. When sweeping the magnetic flux, we observe avoided level crossings in the spectrum, a detailed fingerprint of the spatial distribution of local disorder. Combining these methods, we reconstruct electronic properties of the eigenstates where we observe persistent currents and a strong suppression of conductance with added disorder. Our work describes an accurate method for quantum simulation and paves the way to study novel quantum materials with superconducting qubits.

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