论文标题
具有偏见和非线性相互作用的量子性狂犬模型中的对称性破坏模式，三临界和四倍点
Symmetry breaking patterns, tricriticalities and quadruple points in quantum Rabi model with bias and nonlinear interaction
论文作者
论文摘要
量子狂犬模型（QRM）令人着迷，这不仅是因为其广泛的相关性，而且还因为其少量的量子相变。实际上，QRM中的偏差和非线性耦合都是实验设置中的重要控制参数。我们研究了偏差的相互作用以及在基态处的线性耦合的非线性相互作用，该耦合表现出各种对称性破裂和不同顺序的过渡顺序。在低频限制和有限的频率下，三个临界的几种情况被揭示。我们发现，完整的量子力学效应会导致新颖的过渡，三临界和四倍点，这远远超出了半经典图像。我们通过分析能量竞争和量子状态的基本转换来阐明潜在机制，从而使我们能够提取大多数分析相边界。
Quantum Rabi model (QRM) is fascinating not only because of its broad relevance and but also due to its few-body quantum phase transition. In practice both the bias and the nonlinear coupling in QRM are important controlling parameters in experimental setups. We study the interplay of the bias and the nonlinear interaction with the linear coupling in the ground state which exhibits various patterns of symmetry breaking and different orders of transitions. Several situations of tricriticality are unveiled in the low frequency limit and at finite frequencies. We find that the full quantum-mechanical effect leads to novel transitions, tricriticalities and quadruple points, which are much beyond the semiclassical picture. We clarify the underlying mechanisms by analyzing the energy competitions and the essential changeovers of the quantum states, which enables us to extract most analytic phase boundaries.
