论文标题
约瑟夫森发射在昆多政权中的碳纳米管连接处的崩溃
Collapse of the Josephson emission in a carbon nanotube junction in the Kondo regime
论文作者
论文摘要
我们探测了基于碳纳米管的约瑟夫森连接的高频发射，并将其与其直流约瑟夫森电流进行比较。通过将碳纳米管耦合到片上检测器（超导体 - 绝缘体 - 驱动器连接），通过偶联来探测AC发射。检测器的照片辅助电流的测量可直接访问碳纳米管发出的信号。我们专注于在正常状态中表现出近藤特征的栅极区域，并证明当DC超电流通过Kondo效应增强时，AC Josephson效应会大大降低。该结果与NRG理论进行了比较，并归因于单线基态与双重激发态之间的过渡，该态仅在连接处被电压偏置驱动到平衡外时才能启用。
We probe the high frequency emission of a carbon nanotube based Josephson junction and compare it to its DC Josephson current. The AC emission is probed by coupling the carbon nanotube to an on-chip detector (a Superconductor-Insulator-Superconductor junction), via a coplanar waveguide resonator. The measurement of the photo-assisted current of the detector gives direct access to the signal emitted by the carbon nanotube. We focus on the gate regions that exhibit Kondo features in the normal state and demonstrate that when the DC supercurrent is enhanced by the Kondo effect, the AC Josephson effect is strongly reduced. This result is compared to NRG theory and is attributed to a transition between the singlet ground state and the doublet excited state which is enabled only when the junction is driven out-of-equilibrium by a voltage bias.
