论文标题
Yukawa-Syk模型中的量子相变
Quantum Phase Transition in the Yukawa-SYK Model
论文作者
论文摘要
我们研究了可解决的模型中费米度密度$ν$变化的量子相变，该模型在$ n $ bosons和$ m $ fermions之间随机相互作用，被称为Yukawa-syk模型。我们表明该模型中有两个不同的阶段：一个不可压缩的状态，具有散布的激发和一个异国情调的量子量，非弗米液态状态，指数随$ν$而变化。我们在分析上和数字上表明，这两个状态之间的量子相变是一阶的，因为NFL状态的$ν$范围为$ν$。在极限$ n/m \至\ infty $中，一阶转变变得较弱，渐近地成为二阶，具有异国情调的量子性行为。我们表明，费米子和玻色子在过渡区域表现出高度非常规的光谱行为。
We study the quantum phase transition upon variation of the fermionic density $ν$ in a solvable model with random Yukawa interactions between $N$ bosons and $M$ fermions, dubbed the Yukawa-SYK model. We show that there are two distinct phases in the model: an incompressible state with gapped excitations and an exotic quantum-critical, non-Fermi liquid state with exponents varying with $ν$. We show analytically and numerically that the quantum phase transition between these two states is first-order, as for some range of $ν$ the NFL state has a negative compressibility. In the limit $N/M\to \infty$ the first-order transition gets weaker and asymptotically becomes second-order, with an exotic quantum-critical behavior. We show that fermions and bosons display highly unconventional spectral behavior in the transition region.
