论文标题
超高质量的二维电子系统
Ultra-high quality two-dimensional electron systems
论文作者
论文摘要
仅限于GAAS量子井的二维电子是用于探测电子电子相互作用的标志平台。多年来，这些系统中的样本质量有所改善，已经在这些系统中进行了许多关键观察。在这里，我们通过源材料纯化和GAAS分子束外观真空室设计中的源材料纯化和创新来展示样品质量的突破。我们的样本显示了$ 44 \ times10^6 $ cm $^2 $ /vs的超高移动性，电子密度为$ 2.0 \ times10^{11} $ /cm $ $^2 $。这些结果意味着每10美元^{10} $ ga/作为原子，只有1个残留杂质。这种低杂质浓度的影响是多种多样的。观察到强大的条纹/气泡相，并出现了几个新的分数量子霍尔状态。此外，$ν= 5/2 $状态的激活差距被认为是非 - 亚伯利亚的，并且可能用于拓扑量子计算，它达到了$δ\ simeq820 $ mk。我们预计我们的结果将在二维环境中刺激对相互作用驱动的物理的进一步研究，并显着提高该领域。
Two-dimensional electrons confined to GaAs quantum wells are hallmark platforms for probing electron-electron interaction. Many key observations have been made in these systems as sample quality improved over the years. Here, we present a breakthrough in sample quality via source-material purification and innovation in GaAs molecular beam epitaxy vacuum chamber design. Our samples display an ultra-high mobility of $44\times10^6$ cm$^2$/Vs at an electron density of $2.0\times10^{11}$ /cm$^2$. These results imply only 1 residual impurity for every $10^{10}$ Ga/As atoms. The impact of such low impurity concentration is manifold. Robust stripe/bubble phases are observed, and several new fractional quantum Hall states emerge. Furthermore, the activation gap of the $ν=5/2$ state, which is widely believed to be non-Abelian and of potential use for topological quantum computing, reaches $Δ\simeq820$ mK. We expect that our results will stimulate further research on interaction-driven physics in a two-dimensional setting and significantly advance the field.
