Institute for Experimental and Applied Physics, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany.
Phys Rev Lett. 2018 Jun 15;120(24):246802. doi: 10.1103/PhysRevLett.120.246802.
Using the transversal vibration resonance of a suspended carbon nanotube as a charge detector for its embedded quantum dot, we investigate the case of strong Kondo correlations between a quantum dot and its leads. We demonstrate that even when large Kondo conductance is carried at odd electron number, the charging behavior remains similar between odd and even quantum dot occupations. While the Kondo conductance is caused by higher order processes, a sequential tunneling only model can describe the time-averaged charge. The gate potentials of the maximum current and fastest charge increase display a characteristic relative shift, which is suppressed at increased temperature. These observations agree very well with models for Kondo-correlated quantum dots.
利用悬浮碳纳米管的横向振动共振作为嵌入量子点的电荷探测器，我们研究了量子点与其引线之间存在强 Kondo 相关的情况。我们证明，即使在奇数电子数下存在大的 Kondo 电导率，奇数和偶数量子点占据时的充电行为仍然相似。虽然 Kondo 电导率是由高阶过程引起的，但顺序隧道仅模型可以描述时间平均电荷。最大电流和最快电荷增加的栅极电势显示出特征的相对位移，该位移在增加温度时受到抑制。这些观察结果与 Kondo 相关量子点的模型非常吻合。
