论文标题
双层层中自旋液体的电气检测
Electrical detection of spin liquids in double moiré layers
论文作者
论文摘要
尽管旋转是一个基本的量子数，但测量传统固态系统中的自旋传输非常具有挑战性。这构成了检测包括某些自旋液体在内的有趣量子状态的主要障碍。在本文中，我们提出了一个平台，该平台不仅可以进行自旋传输的电测量，而且可以稳定各种外来量子相。我们的建议涉及两个Moiré超级晶格，这些超晶格是由过渡金属二核苷（TMD）或石墨烯建造的，它们通过薄绝缘层彼此分离。两个库仑耦合的莫伊尔层在适当地对齐时会产生伪赋的自由度。可以从截面或库仑阻力电导率的纯电测量值中访问伪蛋白的运输。此外，这些平台自然会在三角形晶格上使用$ n = 4 \，{\ rm或} \，8 $风味实现Hubbard模型。风味退化激发了大N近似，我们从中获得了不同电子填充物和相关强度下Mott绝缘子的相图。除了传统的阶段（例如伪造的超氟和结晶的绝缘子）外，还发现了包括手性旋转液体和$ u（1）$ spinon fermi表面旋转液体在内的外来阶段，所有这些阶段都将显示此设置中的吸烟枪支电特征。
Although spin is a fundamental quantum number, measuring spin transport in traditional solid state systems is extremely challenging. This poses a major obstacle to detecting interesting quantum states including certain spin liquids. In this paper we propose a platform that not only allows for the electrical measurement of spin transport, but in which a variety of exotic quantum phases may be stabilized. Our proposal involves two moiré superlattices, built from transition metal dichalcogenides (TMD) or graphene, separated from one another by a thin insulating layer. The two Coulomb coupled moiré layers, when suitably aligned, give rise to a layer pseudospin degree of freedom. The transport of pseudospin can be accessed from purely electrical measurements of counter-flow or Coulomb drag conductivity. Furthermore, these platforms naturally realize Hubbard models on the triangular lattice with $N = 4\, {\rm or}\, 8$ flavors. The flavor degeneracy motivates a large-N approximation from which we obtain the phase diagram of Mott insulators at different electron fillings and correlation strengths. In addition to conventional phases such as psuedospin superfluids and crystallized insulators, exotic phases including chiral spin liquids and a $U(1)$ spinon Fermi surface spin liquid are also found, all of which will show smoking gun electrical signatures in this setup.
