论文标题
在金属中抗铁磁性开始时，挑剔的批判性和幽灵费米表面
Deconfined criticality and ghost Fermi surfaces at the onset of antiferromagnetism in a metal
论文作者
论文摘要
我们提出了一个一般的理论框架，使用两层的Ancilla Qubits，以在具有较大费米表面的费米液体和带有电子样的胶状胶片表面的伪造金属之间取消限制性。伪制品金属可以是磁有序的金属，也可以是无磁性的分数式费米液体（FL*）。 A critical 'ghost' Fermi surface emerges (alongside the large electron Fermi surface) at the transition, with the ghost fermions carrying neither spin nor charge, but minimally coupled to $(U(1) \times U(1))/Z_2$ or $(SU(2) \times U(1))/Z_2$ gauge fields. $（u（1）\ times u（1））/z_2 $ case描述了同时的围绕膜分解和磁顺序的发作：两个量规场引起了幽灵费米表面激发之间几乎相等的吸引力和排斥性的相互作用，并且该竞争控制了量子关键性。远离伪造侧的过渡，幽灵费米表面吸收了大型电子费米表面的一部分，并导致霍尔同时发生。我们还找到了一个具有自旋密度波顺序的金属与具有局部矩磁序的金属之间的“不必要的量子临界点”的示例。幽灵费米子在过渡附近贡献了增强的特定热量，也可以在其他热探针中检测到。我们将结果与相关电子化合物的阶段联系起来。
We propose a general theoretical framework, using two layers of ancilla qubits, for deconfined criticality between a Fermi liquid with a large Fermi surface, and a pseudogap metal with a small Fermi surface of electron-like quasiparticles. The pseudogap metal can be a magnetically ordered metal, or a fractionalized Fermi liquid (FL*) without magnetic order. A critical 'ghost' Fermi surface emerges (alongside the large electron Fermi surface) at the transition, with the ghost fermions carrying neither spin nor charge, but minimally coupled to $(U(1) \times U(1))/Z_2$ or $(SU(2) \times U(1))/Z_2$ gauge fields. The $(U(1) \times U(1))/Z_2$ case describes simultaneous Kondo breakdown and onset of magnetic order: the two gauge fields induce nearly equal attractive and repulsive interactions between ghost Fermi surface excitations, and this competition controls the quantum criticality. Away from the transition on the pseudogap side, the ghost Fermi surface absorbs part of the large electron Fermi surface, and leads to a jump in the Hall co-efficient. We also find an example of an "unnecessary quantum critical point" between a metal with spin density wave order, and a metal with local moment magnetic order. The ghost fermions contribute an enhanced specific heat near the transition, and could also be detected in other thermal probes. We relate our results to the phases of correlated electron compounds.
