论文标题
量子点生成的2D热电子的超快能量放松
Ultrafast energy relaxation of quantum dot-generated 2D hot electrons
论文作者
论文摘要
通过一系列的横向磁聚焦实验，我们表明，当由量子点（QD）而不是量子点接触（QPC）产生时，二维电子气体系统中的热电子会经历超快松弛。我们在这里发现，通过非交互式费米气体模型很好地描述了QPC热电子，以高于7.44 MeV的费米水平高达1.5 meV，而QD热电子表现出激发的能量损失二次。能量放松是测试激发的一部分，高达约55％。通过提出的建议，热电子在发射后立即被QD放松，我们提出了一个玩具模型，其中QD及其铅之间的电容耦合导致有限的超快能量放松。
Through a series of transverse magnetic focusing experiments, we show that hot electrons in a two-dimensional electron gas system undergo an ultrafast relaxation when generated by a quantum dot (QD) instead of a quantum point contact (QPC). We find here that QPC hot electrons were well described by the non-interacting Fermi gas model for excitations up to 1.5 meV above the Fermi level of 7.44 meV, whereas QD hot electrons exhibited an energy loss quadratic to the excitation. The energy relaxation was a sizeable fraction of the tested excitations, up to about 55%. With the proposal that the hot electrons are relaxed by the QD immediately after emission, we present a toy model in which a capacitive coupling between the QD and its leads results in a finite, ultrafast energy relaxation.
