近日，法国巴黎萨克雷大学的F. Pierre&A. Anthore及其研究团队取得一项新进展。经过不懈努力，他们实现分数量子霍尔任意子标度维度的观察。相关研究成果已于2024年7月3日在国际权威学术期刊《自然》上发表。

该研究团队揭示了从热噪声到散粒噪声交叉的标度维度，并观察到与预期一致。通过将测量结果拟合至预测的有限温度表达式，研究人员同时获取了准粒子的标度维度和电荷信息，这一方法超越了以往仅聚焦于高偏置散粒噪声区域的电荷研究。在多种标度设定和实验条件下进行的系统性重复分析，证实了填充因子v=1/3、2/5和2/3时出现的分数准粒子与理论预测的尺度维度高度一致。这建立了分数量子霍尔任意子的中心性质，并展示了一个强大的互补窗口，可以研究奇异准粒子。

据悉，在分数量子霍尔体系中出现的非常规准粒子提出了明确观察其奇异性质的挑战。尽管准粒子的分数电荷现象已被证实近30年之久，但其任意量子统计特性的首个确凿证据直到最近才得以浮现。到目前为止，决定准粒子传播动力学的所谓标度维度仍然难以捉摸。特别是，虽然隧道准粒子电流的非线性应该揭示它们的尺度维度，但测量结果与理论不符，可能是因为这种可观察到的结果对非普遍的复杂性不具有鲁棒性。

附：英文原文

Title: Observation of the scaling dimension of fractional quantum Hall anyons

Author: Veillon, A., Piquard, C., Glidic, P., Sato, Y., Aassime, A., Cavanna, A., Jin, Y., Gennser, U., Anthore, A., Pierre, F.

Issue&Volume: 2024-07-03

Abstract: Unconventional quasiparticles emerging in the fractional quantum Hall regime present the challenge of observing their exotic properties unambiguously. Although the fractional charge of quasiparticles has been demonstrated since nearly three decades, the first convincing evidence of their anyonic quantum statistics has only recently been obtained and, so far, the so-called scaling dimension that determines the quasiparticles’ propagation dynamics remains elusive. In particular, while the non-linearity of the tunneling quasiparticle current should reveal their scaling dimension, the measurements fail to match theory, arguably because this observable is not robust to non-universal complications. Here we expose the scaling dimension from the thermal to shot noise crossover, and observe an agreement with expectations. Measurements are fitted to the predicted finite temperature expression involving both the quasiparticles scaling dimension and their charge, in contrast to previous charge investigations focusing on the high bias shot noise regime. A systematic analysis, repeated on multiple constrictions and experimental conditions, consistently matches the theoretical scaling dimensions for the fractional quasiparticles emerging at filling factors v=1/3, 2/5 and 2/3. This establishes a central property of fractional quantum Hall anyons, and demonstrates a powerful and complementary window into exotic quasiparticles.

DOI: 10.1038/s41586-024-07727-z

Source: https://www.nature.com/articles/s41586-024-07727-z