论文标题
在石墨烯中的孔结合分数量子厅状态消失的热平衡
Vanishing thermal equilibration for hole-conjugate fractional quantum Hall states in graphene
论文作者
论文摘要
通过边缘通道的运输负责量子大厅（QH）阶段的传导。拓扑决定了电荷和热传输系数的量化。当不连贯的平衡过程成为主导时，这些事实将其接近可靠的量化值。在这里，我们报告了整数和分数量子霍尔（FQH）阶段的电导和热电导的测量，该阶段已在HBN封装的石墨门控双层石墨烯设备中实现。值得注意的是，对于填充因子的复杂边缘$ν= 5/3 $和$ν= 8/3 $，这对应于部分填充的Landau级别的范式孔偶联FQH相$ν= 2/3 $，我们发现热量平衡消失了。这是令人惊讶的，鉴于同时我们的电导结果表明电荷平衡。这些结果与我们的理论分析一致，指出在强静电相互作用极限的不同热平衡长度。我们的结果阐明了电子二维拓扑阶段中从介质到稳健拓扑主导的运输的微妙性质。
Transport through edge-channels is responsible for conduction in quantum Hall (QH) phases. Topology dictates quantization of both charge and thermal transport coefficients. These turn out to approach robust quantized values when incoherent equilibration processes become dominant. Here, we report on measurements of both electrical and thermal conductances of integer and fractional quantum Hall (FQH) phases, realized in hBN encapsulated graphite gated bilayer graphene devices. Remarkably, for the complex edge at filling factors $ν=5/3$ and $ν=8/3$, which correspond to the paradigmatic hole-conjugate FQH phase $ν=2/3$ of the partially filled Landau level, we find vanishing thermal equilibration. This is striking, given that, at the same time, our results for the electrical conductance indicate efficient charge equilibration. These results are in accord with our theoretical analysis, pointing to a divergent thermal equilibration length in the limit of strong electrostatic interaction. Our results elucidate the subtle nature of the crossover from mesoscopic to robust topology-dominated transport in electronic two-dimensional topological phases.
