A ferronematic slab in external magnetic fields.
A ferronematic slab in external magnetic fields.
复制标题
外部磁场中的铁电板。
作者：
G. Zarubin;M. Bier;S. Dietrich
数值研究了均匀磁化铁磁板在外加磁场与其初始磁化方向平行和反平行时的行为。所采用的数值方法允许确定磁滞曲线，从磁滞曲线可以确定临界磁场强度（即，铁磁样品变得失真的频率）作为系统参数的函数。通过在反平行方向上施加磁场来切换磁化的两种可能的机制被观察到，并且其特征在于在磁化和双折射指向矢之间的耦合常数方面以及在双折射液晶和板的壁的耦合强度方面。适当制备的壁允许人们在一个设置中联合收割机组合两个切换机构，使得人们可以构造其磁化可以可逆地关闭的单元。
The behavior of a uniformly magnetized ferronematic slab is investigated numerically in a situation in which an external magnetic field is applied parallel and antiparallel, respectively, to its initial magnetization direction. The employed numerical method allows one to determine hysteresis curves from which a critical magnetic field strength (i.e., the one at which the ferronematic sample becomes distorted) as a function of the system parameters can be inferred. Two possible mechanisms of switching the magnetization by applying a magnetic field in the antiparallel direction are observed and characterized in terms of the coupling constant between the magnetization and the nematic director and in terms of the coupling strength of the nematic liquid crystal and the walls of the slab. Suitably prepared walls allow one to combine both switching mechanisms in one setup, such that one can construct a cell, the magnetization of which can be reversibly switched off.