Semiclassical approach to spin dynamics of a ferromagnetic S = 1 chain  

作　　者：李承晨 崔祎 于伟强 俞榕 Chengchen Li;Yi Cui;Weiqiang Yu;Rong Yu(Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices,Renmin University of China,Beijing 100872,China;Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education),Renmin University of China,Beijing 100872,China)

机构地区：[1]Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices,Renmin University of China,Beijing 100872,China [2]Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education),Renmin University of China,Beijing 100872,China

出　　处：《Chinese Physics B》2024年第6期95-100,共6页中国物理B（英文版）

基　　金：Project supported by the National Key R&D Program of China (Grant No. 2023YFA1406500);the National Natural Science Foundation of China (Grant Nos. 12334008, 12174441,12134020, and 12374156)。

摘　　要：Motivated by recent experimental progress on the quasi-one-dimensional quantum magnet Ni Nb2O6, we study the spin dynamics of an S = 1 ferromagnetic Heisenberg chain with single-ion anisotropy by using a semiclassical molecular dynamics approach. This system undergoes a quantum phase transition from a ferromagnetic to a paramagnetic state under a transverse magnetic field, and the magnetic response reflecting this transition is well described by our semiclassical method.We show that at low temperature the transverse component of the dynamical structure factor depicts clearly the magnon dispersion, and the longitudinal component exhibits two continua associated with single-and two-magnon excitations,respectively. These spin excitation spectra show interesting temperature dependence as effects of magnon interactions. Our findings shed light on the experimental detection of spin excitations in a large class of quasi-one-dimensional magnets.

关 键 词：one-dimensional ferromagnetism spin dynamics magnon excitation molecular dynamics 

分 类 号：O469[理学—凝聚态物理]