论文标题
基于较强的互动和多体动力解耦的小型逻辑量子架构
Small logical qubit architecture based on strong interactions and many-body dynamical decoupling
论文作者
论文摘要
我们提出了一种新型的超导逻辑量子架构，称为冷Echo Qubit（CEQ），该结构能够保留比其任何组件部分更长的时间表的量子信息。 CEQ完全自主运行，不需要测量或反馈，并且与相对强大的相互作用元素兼容，从而可以在多个CEQ之间进行快速，高富达逻辑的门。它的量子状态由强相互作用和微波驾驶的组合进行保护，该组合实现了一种多体动力学脱钩的形式以抑制相位噪声。基于仔细的理论分析和数值模拟的估计值与当前的最新水平相比，可以预测生命和栅极保真度的改善，或者在基本连贯性方面没有改善。在这里，我们使用一对通过共享的相互电感分解的磁盘量子置量的CEQ的最简单实现。虽然不一定是最佳的实现，但最容易在实验上测试，并且应该表现出超越收支平衡的连贯性（与其组件的限制相干时间相比）。还提出了更复杂的三节点电路。预计它的两流头国阵线的连贯性将大约翻一番。
We propose a novel superconducting logical qubit architecture, called the Cold Echo Qubit (CEQ), which is capable of preserving quantum information for much longer timescales than any of its component parts. The CEQ operates fully autonomously, requiring no measurement or feedback, and is compatible with relatively strong interaction elements, allowing for fast, high fidelity logical gates between multiple CEQ's. Its quantum state is protected by a combination of strong interactions and microwave driving, which implements a form of many-body dynamical decoupling to suppress phase noise. Estimates based on careful theoretical analysis and numerical simulations predict improvements in lifetimes and gate fidelities by an order of magnitude or more compared to the current state of the art, assuming no improvements in base coherence. Here, we consider the simplest possible implementation of the CEQ, using a pair of fluxonium qubits shunted through a shared mutual inductance. While not necessarily the best possible implementation, it is the easiest to test experimentally and should display coherence well past breakeven (as compared to the limiting coherence times of its components). A more complex three-node circuit is also presented; it is expected to roughly double the coherence of its two-fluxonium counterpart.
