Mesquita P D, Moura A R
J Phys Condens Matter. 2020 Jul 15;32(30):305802. doi: 10.1088/1361-648X/ab83b2. Epub 2020 Mar 26.
Research in spintronics has attracted much attention in the last few years due to the technological progress in generating and manipulating spin currents in miniaturized devices. Notwithstanding dissipative effects are inherent to experiments, in many theoretical works the damping of spin waves is included later by phenomenological arguments or even disregarded. Among the many techniques that have been used to treat magnetic models, bosonic representations is one of them. In this work, we chose the Holstein-Primakoff bosonic formalism to treat a ferromagnetic model with a priori inclusion of the damping term. Damping is included through a non-Hermitian term in the Hamiltonian and we showed that the well-known coherent state formalism can be generalized to properly represent the dissipative magnon model. The obtained results are then used to describe the precession magnetization in spintronic experiments, as the spin pumping process.
在过去几年中，由于在小型化器件中产生和操纵自旋电流的技术进步，自旋电子学研究备受关注。尽管耗散效应在实验中是固有的，但在许多理论工作中，自旋波的阻尼后来是通过唯象论证纳入的，甚至被忽略了。在用于处理磁模型的众多技术中，玻色子表示是其中之一。在这项工作中，我们选择了霍尔斯坦 - 普里马科夫玻色子形式来处理一个先验包含阻尼项的铁磁模型。通过哈密顿量中的一个非厄米项纳入阻尼，并且我们表明著名的相干态形式可以被推广以恰当地表示耗散磁振子模型。然后将所获得的结果用于描述自旋电子学实验中的进动磁化，即自旋泵浦过程。
