论文标题
降低放射性对深度设施中量子电路的影响
Reducing the impact of radioactivity on quantum circuits in a deep-underground facility
论文作者
论文摘要
随着超导电路的量子相干时间从纳秒秒增加到数百微秒，目前是量子信息处理的领先平台之一。但是，连贯性需要通过数量级进一步改进，以减少当前误差校正方案的高度硬件开销。达到这个目标会取决于降低库珀对，所谓的准粒子的密度。在这里，我们表明环境放射性是非平衡准颗粒的重要来源。此外，电离辐射在同一芯片上引入了与时间相关的准粒子突发，进一步使量子误差校正复杂化。在深层铅屏蔽的低温恒温器中运行，将准颗粒的爆发率降低了五十倍，并将耗散降低到一个因子四，从而显示了辐射减少在未来的固态量子硬件中的重要性。
As quantum coherence times of superconducting circuits have increased from nanoseconds to hundreds of microseconds, they are currently one of the leading platforms for quantum information processing. However, coherence needs to further improve by orders of magnitude to reduce the prohibitive hardware overhead of current error correction schemes. Reaching this goal hinges on reducing the density of broken Cooper pairs, so-called quasiparticles. Here, we show that environmental radioactivity is a significant source of nonequilibrium quasiparticles. Moreover, ionizing radiation introduces time-correlated quasiparticle bursts in resonators on the same chip, further complicating quantum error correction. Operating in a deep-underground lead-shielded cryostat decreases the quasiparticle burst rate by a factor fifty and reduces dissipation up to a factor four, showcasing the importance of radiation abatement in future solid-state quantum hardware.
