Observation of excited states in a graphene quantum dot
Observation of excited states in a graphene quantum dot
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DOI：
10.1063/1.3064128
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发表时间：
2009-01-05
影响因子：
4
通讯作者：
Ensslin, K.
中科院分区：
文献类型：
--
作者：
Schnez, S.;Molitor, F.;Ensslin, K.
我们证明了单层石墨烯量子点中的激发态可以通过直接输运实验检测到。库仑金刚石测量显示了通过激发态的顺序隧穿的明显特征。此外，在金刚石区域的非弹性共隧穿的发病可以被检测到。对于低磁场，单粒子能级的位置以穿透点区域的通量量子的尺度波动。对于更高的磁场，观察到的过渡到朗道能级的形成。基于石墨烯的线性能量-动量关系的估计给出了我们设备的10阶载流子数。
We demonstrate that excited states in single-layer graphene quantum dots can be detected via direct transport experiments. Coulomb diamond measurements show distinct features of sequential tunneling through an excited state. Moreover, the onset of inelastic cotunneling in the diamond region could be detected. For low magnetic fields, the positions of the single-particle energy levels fluctuate on the scale of a flux quantum penetrating the dot area. For higher magnetic fields, the transition to the formation of Landau levels is observed. Estimates based on the linear energy-momentum relation of graphene give carrier numbers of the order of 10 for our device.