Certification of spin-based quantum simulators
Certification of spin-based quantum simulators
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DOI：
10.1103/physreva.101.052344
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发表时间：
2019-05
影响因子：
2.9
通讯作者：
A. Bayat;B. Voisin;G. Buchs;J. Salfi;S. Rogge;S. Bose
中科院分区：
文献类型：
--
作者：
A. Bayat;B. Voisin;G. Buchs;J. Salfi;S. Rogge;S. Bose
量子模拟器是一种可控的工程设备，旨在模拟复杂的、经典的难以处理的量子系统。一个关键的挑战是证明模拟器是否真的模拟了感兴趣的哈密顿量。这一验证步骤需要将模拟器的输出与已知答案进行比较，这通常限于小系统，因为希尔伯特空间的指数尺度。这里，在基于Fermi-Hubbard自旋的模拟模拟器的背景下，我们提出了一种模块化的多体自旋到电荷转换方案，该方案与系统的大小和要区分的低能本征态的数目成线性关系。我们的协议是基于一维自旋链在不同失谐势下进行的全局电荷态测量。在基于半导体的系统中，我们确定了绝热失谐链的现实条件，以便在保持电荷相干性的同时避免状态混合。具有零能隙的大型模拟器，包括2D阵列，可以逐个块地进行认证，许多测量值仅随系统大小线性调整。
Quantum simulators are engineered devices controllably designed to emulate complex and classically intractable quantum systems. A key challenge is to certify whether the simulator truly mimics the Hamiltonian of interest. This certification step requires the comparison of a simulator's output to a known answer, which is usually limited to small systems due to the exponential scaling of the Hilbert space. Here, in the context of Fermi-Hubbard spin-based analogue simulators, we propose a modular many-body spin to charge conversion scheme that scales linearly with both the system size and the number of low-energy eigenstates to discriminate. Our protocol is based on the global charge state measurement of a 1D spin chain performed at different detuning potentials along the chain. In the context of semiconductor-based systems, we identify realistic conditions for detuning the chain adiabatically in order to avoid state mixing while preserving charge coherence. Large simulators with vanishing energy gaps, including 2D arrays, can be certified block-by-block with a number of measurements scaling only linearly with the system size.