论文标题
蜂窝亲块晶格中重型准颗粒的分解：一项量子蒙特卡洛研究
Breakdown of heavy quasiparticles in a honeycomb Kondo lattice: A quantum Monte Carlo study
论文作者
论文摘要
我们表明，对于蜂窝晶格上半填充的近藤晶格型号，在磁性有序阶段内，在小昆多耦合$ j_k $上发生了昆多故障。我们的结论基于所谓的复合费米光谱函数的辅助场量子蒙特卡洛模拟。在近托模型的U（1）量规理论公式中，很明显，希格斯机制决定了光谱函数中共振的重量。对于蜂窝晶格，我们观察到，对于小$ j_k $，准颗粒杆让位于不连贯的光谱重量，但对于方格的定义仍然很好。我们的结果提供了一个明确的示例，其中磁性转换和重型准颗粒的分解被脱离，如Yb（rh $ _ {0.93} $ co $ _ {0.07} $）$ _ 2 $ _ 2 $ _ 2 $ si $ _2 $ [Friedemann等人，Nat。物理。 \ textbf {5}，465（2009）]。
We show that for the half-filled Kondo lattice model on the honeycomb lattice a Kondo breakdown occurs at small Kondo couplings $J_k$ within the magnetically ordered phase. Our conclusions are based on auxiliary field quantum Monte Carlo simulations of the so-called composite fermion spectral function. Within a U(1) gauge theory formulation of the Kondo model, it becomes apparent that a Higgs mechanism dictates the weight of the resonance in the spectral function. For the honeycomb lattice we observe that for small $J_k$ the quasiparticle pole gives way to incoherent spectral weight but it remains well defined for the square lattice. Our result provides an explicit example where the magnetic transition and the breakdown of heavy quasiparticles are detached as observed in Yb(Rh$_{0.93}$Co$_{0.07}$)$_2$Si$_2$ [Friedemann et al., Nat. Phys. \textbf{5}, 465 (2009)].
