发表机构
Department of Physics and Astronomy, UCL（伦敦大学学院物理与天文系）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出一种四能级架构，利用微波腔实现中性原子量子比特的长程门，通过双色拉曼门抑制衰变，保真度达0.997，并将纠错轮缩短至2.3-4.8倍。
AI 中文摘要
中性原子阵列中的高保真双量子比特门依赖于里德伯阻塞，该机制本质上是短程的，需要通过原子穿梭来实现长程连接。我们提出了一种四能级架构，其中典型的基态量子比特可利用其长寿命，而里德伯态与微波腔耦合，从而实现腔介导的长程门。我们首先研究了两种既有协议的热依赖性，即Tavis-Cummings模型固有的色散iSWAP门和通过驱动腔产生的受控相位门。我们在里德伯衰变、热光子、有限腔线宽的存在下对其进行模拟，并得到了伴随闭式界限的保真度。然后，我们引入了双色拉曼门，该门仅虚布居里德伯态并抵消色散位移，以减轻原子和腔的衰变，实现了$F = 0.997$的保真度。最后，我们考虑了微波腔中的全光镊阵列，并表明使用腔介导门来闭合环面码的周期边界，对于实际阵列尺寸，可将纠错轮缩短2.3倍。这随后被应用于更广泛的二元自行车码族，我们发现它可将粗码的一轮缩短4.8倍。
英文摘要
High-fidelity two-qubit gates in neutral-atom arrays rely on the Rydberg blockade, which is intrinsically short ranged and requires long range connectivity to be achieved through atom shuttling. We propose a four level architecture, where the typical ground state qubit can be leveraged for its long lifetime and the Rydberg states couple to a microwave cavity, allowing for long range cavity mediated gates. We first find the thermal dependence of two established protocols, the dispersive iSWAP native to the Tavis-Cummings model and the Controlled phase gate generated from driving the cavity. We simulate them under the presence of Rydberg decay, thermal photons, finite cavity linewidth and find fidelities which accompany closed form bounds. We then introduce the bichromatic Raman gate, which only virtually populates the Rydberg states and cancels dispersive shifts to mitigate both atomic and cavity decay, achieving a fidelity of $F = 0.997$. Finally, we consider a full optical tweezer array in a microwave cavity, and show that using a cavity mediated gate to close the periodic boundaries of the toric code shortens an error correction round by a factor of 2.3 for realistic array sizes. This was then applied to the wider family of Bivariate bicycle codes, and we find that it shortens a round of the gross code by a factor of 4.8.
Comments14 pages
