论文标题
通过栅极反射法和自旋依赖性隧穿的CMOS量子点的自旋读数
Spin readout of a CMOS quantum dot by gate reflectometry and spin-dependent tunnelling
论文作者
论文摘要
硅旋转Qubits是实现大规模量子处理器的有前途的候选人，从而受益于磁性安静的宿主材料以及利用成熟的硅设备制造行业的前景。我们报告了在单个栅极定义的量子点中对电子自旋的测量，该量子点是使用CMOS兼容过程以300 mm晶圆刻度制造的。为了进行读数，我们采用了与自旋依赖性隧道结合使用辐射闸门反射测量法测量的低英尺单铅量子点电荷传感器。我们使用此技术在两个设备中展示了旋转读数，使用激发状态光谱在0.5-0.7 MEV范围内获得山谷分割，并测量1特斯拉的最大电子自旋松弛时间（$ t_1 $）为$ 9 \ pm 3 $ s。这些漫长的寿命表明，此处采用的硅纳米线几何形状和制造过程对量子设备显示了很大的希望，而此处演示的旋转方法非常适合各种可扩展的架构。
Silicon spin qubits are promising candidates for realising large scale quantum processors, benefitting from a magnetically quiet host material and the prospects of leveraging the mature silicon device fabrication industry. We report the measurement of an electron spin in a singly-occupied gate-defined quantum dot, fabricated using CMOS compatible processes at the 300 mm wafer scale. For readout, we employ spin-dependent tunneling combined with a low-footprint single-lead quantum dot charge sensor, measured using radiofrequency gate reflectometry. We demonstrate spin readout in two devices using this technique, obtaining valley splittings in the range 0.5-0.7 meV using excited state spectroscopy, and measure a maximum electron spin relaxation time ($T_1$) of $9 \pm 3$ s at 1 Tesla. These long lifetimes indicate the silicon nanowire geometry and fabrication processes employed here show a great deal of promise for qubit devices, while the spin-readout method demonstrated here is well-suited to a variety of scalable architectures.
