Haghshenasfard Zahra, Cottam Michael G
Department of Physics and Astronomy, The University of Western Ontario, London, Ontario N6A 3K7, Canada.
J Phys Condens Matter. 2017 Feb 1;29(4):045803. doi: 10.1088/1361-648X/29/4/045803. Epub 2016 Nov 29.
Theoretical studies are reported for the statistical properties of a microwave-driven interacting magnon system. Both the magnetic dipole-dipole and the exchange interactions are included and the theory is developed for the case of parallel pumping allowing for the inclusion of the nonlinear processes due to the four-magnon interactions. The method of second quantization is used to transform the total Hamiltonian from spin operators to boson creation and annihilation operators. By using the coherent magnon state representation we have studied the magnon occupation number and the statistical behavior of the system. In particular, it is shown that the nonlinearities introduced by the parallel pumping field and the four-magnon interactions lead to non-classical quantum statistical properties of the system, such as magnon squeezing. Also control of the collapse-and-revival phenomena for the time evolution of the average magnon number is demonstrated by varying the parallel pumping amplitude and the four-magnon coupling.
报道了关于微波驱动的相互作用磁振子系统统计特性的理论研究。研究中同时考虑了磁偶极 - 偶极相互作用和交换相互作用，并针对平行泵浦的情况发展了理论，该理论考虑了由于四磁振子相互作用而产生的非线性过程。采用二次量子化方法将总哈密顿量从自旋算符转换为玻色子产生和湮灭算符。通过使用相干磁振子态表示，我们研究了磁振子占据数和系统的统计行为。特别地，研究表明平行泵浦场和四磁振子相互作用引入的非线性导致了系统的非经典量子统计特性，如磁振子压缩。此外，通过改变平行泵浦幅度和四磁振子耦合，展示了对平均磁振子数时间演化的崩塌 - 复苏现象的控制。
