A spin-1/2 Ising–Heisenberg branched chain constituted by regularly alternating Ising spins and Heisenberg dimers involving an additional side branching is exactly solved in a magnetic field by the transfer-matrix method. The spin-1/2 Ising–Heisenberg branched chain involves two different Ising and one Heisenberg coupling constants. The overall ground-state phase diagram is formed by three different ground states emergent depending on a mutual interplay between the magnetic field and three considered coupling constants: the modulated quantum antiferromagnetic phase, the quantum ferrimagnetic phase, and the classical ferromagnetic phase. It is shown that the interaction anisotropy connected to two different Ising coupling constants substantially influences a breakdown of the intermediate one-half magnetization plateau, which represents a macroscopic manifestation of the quantum ferrimagnetic phase.

由规则交替的伊辛自旋和海森堡二聚体构成的自旋 1/2 伊辛-海森堡支链，通过转移矩阵方法在磁场中精确求解。自旋 1/2 Ising-Heisenberg 支链涉及两个不同的 Ising 和一个 Heisenberg 耦合常数。整个基态相图由三个不同的基态形成，具体取决于磁场和三个考虑的耦合常数之间的相互作用：调制量子反铁磁相、量子亚铁磁相和经典铁磁相。结果表明，与两个不同的 Ising 耦合常数相关的相互作用各向异性显着影响中间二分之一磁化平台的击穿，