论文标题
石墨烯分数量子霍尔点接触中的通用性手性Luttinger液体行为
Universal chiral Luttinger liquid behavior in a graphene fractional quantum Hall point contact
论文作者
论文摘要
Luttinger液体理论描述了一维导体，该理论预测了势力抑制费米水平附近状态的密度。在一般情况下，缩放指数是非宇宙的，但预计将对分数量子霍尔效应的手性边缘状态进行量化。在这里，我们报告了连接整数和分数量子霍尔边缘状态的点触点的电导测量。在弱耦合时，我们观察到预测的通用二次缩放，并使用温度和电压。在强耦合时，电导饱和至E^2/2H，这是由在点接触处的分数化准粒子的完美反射引起的。我们使用强耦合物理学来实现几乎无耗散的直流电压升压变压器，其增益直接来自电荷的拓扑分数。
One dimensional conductors are described by Luttinger liquid theory, which predicts a power-law suppression of the density of states near the Fermi level. The scaling exponent is non-universal in the general case, but is predicted to be quantized for the chiral edge states of the fractional quantum Hall effect. Here, we report conductance measurements across a point contact linking integer and fractional quantum Hall edge states. At weak coupling, we observe the predicted universal quadratic scaling with temperature and voltage. At strong coupling, the conductance saturates to e^2/2h, arising from perfect Andreev reflection of fractionalized quasi-particles at the point contact. We use the strong coupling physics to realize a nearly dissipationless DC voltage step-up transformer, whose gain of 3/2 arises directly from topological fractionalization of electrical charge.
