论文标题
可调式双层石墨烯半学中的层间电子孔摩擦
Interlayer electron-hole friction in tunable twisted bilayer graphene semimetal
论文作者
论文摘要
电荷中性导电系统代表了一类具有电子孔（E-H）相互作用的异常特性的材料。根据准颗粒的统计，带结构和设备几何形状这些物质的半金属阶段可以具有对外部场的非常规响应，这些响应通常是在单粒子物理学方面经常反抗简单解释的。在这里，我们表明，小角度扭曲的双层石墨烯（SA-TBG）提供了一个高度可调的系统，可以在其中探索相互作用的限制电子传导。通过采用双门控装置架构，我们将设备从非脱位电荷中性的狄拉克流体调整为补偿的两种组件E-H费米液体，在该液体上，空间分离的电子和孔经历了强烈的相互摩擦。通过T^2电阻率准确地遵循我们发展的E-H阻力理论，可以揭示这种摩擦。我们的结果提供了一本教科书说明，说明了不同相互作用受限的运输方式之间的平稳过渡，并阐明了中性SA-TBG的传导机制。
Charge-neutral conducting systems represent a class of materials with unusual properties governed by electron-hole (e-h) interactions. Depending on the quasiparticles' statistics, band structure, and device geometry these semimetallic phases of matter can feature unconventional responses to external fields that often defy simple interpretations in terms of single-particle physics. Here we show that small-angle twisted bilayer graphene (SA-TBG) offers a highly-tunable system in which to explore interactions-limited electron conduction. By employing a dual-gated device architecture we tune our devices from a non-degenerate charge-neutral Dirac fluid to a compensated two-component e-h Fermi liquid where spatially separated electrons and holes experience strong mutual friction. This friction is revealed through the T^2 resistivity that accurately follows the e-h drag theory we develop. Our results provide a textbook illustration of a smooth transition between different interaction-limited transport regimes and clarify the conduction mechanisms in charge-neutral SA-TBG.
