标题： 带有爪子的伪装自由费米子模型 显示英文标题

标题： A free fermions in disguise model with claws

摘要： 最近，发现了几种自旋链模型，这些模型可以表示为“伪装的自由费米子”。 还建立了一种图论处理方法，给出了自由费米子可解性的充分条件。 这些条件涉及哈密顿量所谓的挫折图的一个特定性质，即它必须是爪-free的。 此外，一组充分条件还要求不存在所谓的偶洞。 在本文中，我们提出了一种具有伪装自由费米子的模型，其中挫折图同时包含爪和偶洞。 特殊的耦合常数关系确保了自由费米子的性质仍然成立。 该模型的转移矩阵在一种特殊情况下可以因式分解，从而证明了由本文两位作者最近发表的一种特殊量子电路的假设自由费米子性质。 这是第一个同时包含爪和偶洞的伪装自由费米子的例子。 显示英文摘要

摘要： Recently, several spin chain models have been discovered that admit solutions in terms of "free fermions in disguise." A graph-theoretical treatment of such models was also established, giving sufficient conditions for free fermionic solvability. These conditions involve a particular property of the so-called frustration graph of the Hamiltonian, namely that it must be claw-free. Additionally, one set of sufficient conditions also requires the absence of so-called even holes. In this paper, we present a model with disguised free fermions where the frustration graph contains both claws and even holes. Special relations between coupling constants ensure that the free fermionic property still holds. The transfer matrix of this model can be factorized in a special case, thereby proving the conjectured free fermionic nature of a special quantum circuit published recently by two of the present authors. This is the first example of free fermions in disguise with both claws and even holes simultaneously.