Nanometer Structure Consortium, Lund University, Box 118, 221 00 Lund, Sweden.
Phys Rev Lett. 2010 May 7;104(18):186804. doi: 10.1103/PhysRevLett.104.186804. Epub 2010 May 4.
The large, level-dependent g factors in an InSb nanowire quantum dot allow for the occurrence of a variety of level crossings in the dot. While we observe the standard conductance enhancement in the Coulomb blockade region for aligned levels with different spins due to the Kondo effect, a vanishing of the conductance is found at the alignment of levels with equal spins. This conductance suppression appears as a canyon cutting through the web of direct tunneling lines and an enclosed Coulomb blockade region. In the center of the Coulomb blockade region, we observe the predicted correlation-induced resonance. Our findings are supported by numerical and analytical calculations.
InSb 纳米线量子点中的大、与能级相关的 g 因子使得在量子点中出现了多种能级交叉现象。虽然我们观察到由于 Kondo 效应,不同自旋的能级对齐时在库仑阻塞区域会出现标准的电导增强,但在自旋相同的能级对齐时,电导会消失。这种电导抑制表现为一个峡谷,穿过直接隧道线和封闭的库仑阻塞区域的网络。在库仑阻塞区域的中心,我们观察到了预测的关联诱导共振。我们的发现得到了数值和分析计算的支持。