论文标题
蜂窝状抗fiferromagnet中的价键顺序与量子声子耦合
Valence-Bond Order in a Honeycomb Antiferromagnet Coupled to Quantum Phonons
论文作者
论文摘要
我们使用精确的量子蒙特卡洛模拟来证明抗磁磁性su（2）旋转的néel基态 - $ \ frac {1} {2} $ heisenberg模型可以通过耦合以量子声子破坏。我们发现，具有kekulé秩序的价值明确的一阶转变，而不是骨化的量子临界点。但是，量子晶格波动可以推动向弱的一阶转变，从而揭示了通过相互作用的延迟的过渡性可调性。与一维情况相反，我们在绝热制度中的相图在质量上与挫败的$ J_1 $ -J_2 $模型在质量上不同。我们的结果表明，与键合子的耦合可以在狄拉克系统中诱导kekulé秩序。
We use exact quantum Monte Carlo simulations to demonstrate that the Néel ground state of an antiferromagnetic SU(2) spin-$\frac{1}{2}$ Heisenberg model on the honeycomb lattice can be destroyed by a coupling to quantum phonons. We find a clear first-order transition to a valence-bond-solid state with Kekulé order instead of a deconfined quantum critical point. However, quantum lattice fluctuations can drive the transition towards weakly first-order, revealing a tunability of the transition by the retardation of the interaction. In contrast to the one-dimensional case, our phase diagram in the adiabatic regime is qualitatively different from the frustrated $J_1$-$J_2$ model. Our results suggest that a coupling to bond phonons can induce Kekulé order in Dirac systems.
