论文标题
偶极量子模拟器中的多部分纠缠状态
Multipartite entangled states in dipolar quantum simulators
论文作者
论文摘要
Qubits集团中多方纠缠状态的可扩展产生是量子设备的基本功能,因为这些状态是纠缠基础研究以及应用任务的基本研究的重要资源。在这里,我们专注于$ u(1)$对称的汉密尔顿人,用于具有偶性相互作用的Qubits,这是一种在几个最先进的量子模拟平台中实现的晶格旋转模型的模型,包括Rydberg-Atom阵列具有共振互动。从理论上讲,利用精确和变异的模拟,我们表明,这种晶格自旋汉密尔顿产生的非平衡动力学具有基本特征,即单轴扭转模型,即使用$ u(1)$对称性的最简单的交互性集体旋转模型。受偶性汉密尔顿(Hamiltonian)控制的进化产生了一系列多部分纠缠状态 - 自旋方状态,Schrödinger的猫状态和相干旋转状态的多组分叠加。调查最多$ n = 144 $ Qubits的系统,我们观察到与计量学直接相关的这些状态的纠缠特征的完全可扩展性,即在进化时间$ {\ cal o}(n^{1/3})$; Heisenberg的旋转平价对全球旋转的敏感性的缩放量表达到了$ {\ cal o}(n)$。我们的结果表明,最先进的量子仿真平台(例如Rydberg-Atom阵列)的本地汉密尔顿动力学可以充当多方纠缠的强大来源。
The scalable production of multipartite entangled states in ensembles of qubits is a fundamental function of quantum devices, as such states are an essential resource both for fundamental studies on entanglement, as well as for applied tasks. Here we focus on the $U(1)$ symmetric Hamiltonians for qubits with dipolar interactions -- a model realized in several state-of-the-art quantum simulation platforms for lattice spin models, including Rydberg-atom arrays with resonant interactions. Making use of exact and variational simulations, we theoretically show that the non-equilibrium dynamics generated by this lattice spin Hamiltonian shares fundamental features with that of the one-axis-twisting model, namely the simplest interacting collective-spin model with $U(1)$ symmetry. The evolution governed by the dipolar Hamiltonian generates a cascade of multipartite entangled states -- spin-squeezed states, Schrödinger's cat states, and multi-component superpositions of coherent spin states. Investigating systems with up to $N=144$ qubits, we observe full scalability of the entanglement features of these states directly related to metrology, namely scalable spin squeezing at an evolution time ${\cal O}(N^{1/3})$; and Heisenberg scaling of sensitivity of the spin parity to global rotations for cat states reached at times ${\cal O}(N)$. Our results suggest that the native Hamiltonian dynamics of state-of-the-art quantum simulation platforms, such as Rydberg-atom arrays, can act as a robust source of multipartite entanglement.