论文标题
由FEMTO秒光脉冲诱导的超快速自旋nematic和铁电相变
Ultrafast spin-nematic and ferroelectric phase transitions induced by femto-second light pulses
论文作者
论文摘要
使用模型的hamiltonian模拟了锰矿$ \ rm pr_ {1/3} ca__ {2/3} mno_3 $的光学诱导的相变，该{2/3} MNO_3 $模拟了模型的哈密顿量，该模型捕获了强烈相关的电荷，轨道，轨道，晶格，lattice和自由度的动力学。它的参数已从第一原理计算中提取。除了FEMTO秒光脉冲的临界强度之外，该材料还经历了从非共线到共线性抗抗铁磁相的超快速和非热磁相的过渡。轻脉冲根据光偏度振兴，有选择地激发自旋nematic或铁电期。该行为可以追溯到MN诱导者之间的光学诱导的铁磁耦合，即在三个MN位点上被定位的极性子。极化将二极化晶体的聚合分为决定目标相的铁磁链的不同模式。
Optically-induced phase transitions of the manganite $\rm Pr_{1/3}Ca_{2/3}MnO_3$ have been simulated using a model Hamiltonian, that captures the dynamics of strongly correlated charge, orbital, lattice, and spin degrees of freedom. Its parameters have been extracted from first-principles calculations. Beyond a critical intensity of a femto-second light pulse, the material undergoes ultra-fast and non-thermal magnetic phase transition from a non-collinear to collinear antiferromagnetic phases. The light-pulse excites selectively either a spin-nematic or a ferroelectric phase depending on the light-polarization. The behavior can be traced to an optically induced ferromagnetic coupling between Mn-trimers, i.e. polarons which are delocalized over three Mn-sites. The polarization guides the polymerization of the polaronic crystal into distinct patterns of ferromagnetic chains determining the target phase.
