论文标题
基于可调ZZ互操作的条件性相对门的实施
Implementation of Conditional-Phase Gates based on tunable ZZ-Interactions
论文作者
论文摘要
表现出低串扰的高富达两分之二的门是基于门的量子信息处理的必不可少的基础。在超导电路中，两个Qubit大门通常基于RF控制的相互作用或量子频率的原位可调性。在这里，我们使用两个量子位之间的可调横kerr型ZZ相互作用提出了一种替代方法，我们通过通量可调的耦合器元素实现。我们在三个数量级上控制ZZ耦合率，以执行快速（38 ns），高对比度，低泄漏（0.14％）条件性相位CZ门，而富达度为97.9％，而无需依靠与非竞争状态的谐振相互作用。此外，通过利用ZZ耦合的直接性质，我们仅通过调整单个控制参数来轻松访问整个条件阶段门家族。
High fidelity two-qubit gates exhibiting low crosstalk are essential building blocks for gate-based quantum information processing. In superconducting circuits two-qubit gates are typically based either on RF-controlled interactions or on the in-situ tunability of qubit frequencies. Here, we present an alternative approach using a tunable cross-Kerr-type ZZ-interaction between two qubits, which we realize by a flux-tunable coupler element. We control the ZZ-coupling rate over three orders of magnitude to perform a rapid (38 ns), high-contrast, low leakage (0.14 %) conditional-phase CZ gate with a fidelity of 97.9 % without relying on the resonant interaction with a non-computational state. Furthermore, by exploiting the direct nature of the ZZ-coupling, we easily access the entire conditional-phase gate family by adjusting only a single control parameter.
