论文标题
Bogoliubov de Gennes系统中拓扑放大器的选择规则
Selection Rule for Topological Amplifiers in Bogoliubov de Gennes Systems
论文作者
论文摘要
动力不稳定性是Bogoliubov de geenes（BDG）汉密尔顿人描述的骨系统的固有特征。由于它会导致BDG系统崩溃，因此通常认为应该避免使用它。最近，已经付出了很多努力来利用这种不稳定，从而使创建具有稳定的散装带但不稳定的边缘模式的拓扑放大器可以以指数级的快速速度填充。我们提出了一个定理，该定理是通过在保存零件和BDG Hamiltonian的数量不强制性部分之间的非常规的换向器方面确定能量足够远离零的稳定性。我们将定理应用于Galilo等人的模型的概括。 [物理。 Rev. Lett，115，245302（2015）]，用于通过淬火过程在蜂窝晶格中在相互作用的自旋-1原子系统中创建拓扑放大器。我们使用此模型来说明非常规换向器的消失如何为系统选择对称性，从而使其稳定状态在（弱）配对相互作用上保持稳定。我们发现，只要保留时间逆转对称性，我们的系统就可以像拓扑放大器一样起作用，即使存在破坏反转对称性的现场势头的存在。
Dynamical instability is an inherent feature of bosonic systems described by the Bogoliubov de Geenes (BdG) Hamiltonian. Since it causes the BdG system to collapse, it is generally thought that it should be avoided. Recently, there has been much effort to harness this instability for the benefit of creating a topological amplifier with stable bulk bands but unstable edge modes which can be populated at an exponentially fast rate. We present a theorem for determining the stability of states with energies sufficiently away from zero, in terms of an unconventional commutator between the number conserving part and number nonconserving part of the BdG Hamiltonian. We apply the theorem to a generalization of a model from Galilo et al. [Phys. Rev. Lett, 115, 245302(2015)] for creating a topological amplifier in an interacting spin-1 atom system in a honeycomb lattice through a quench process. We use this model to illustrate how the vanishing of the unconventional commutator selects the symmetries for a system so that its bulk states are stable against (weak) pairing interactions. We find that as long as time reversal symmetry is preserved, our system can act like a topological amplifier, even in the presence of an onsite staggered potential which breaks the inversion symmetry.
