论文标题
螺旋介质的平面波和扭曲光子的散射
Scattering of plane-wave and twisted photons by helical media
论文作者
论文摘要
通过在分散介质中使用量子电动力学，我们描述了平面波和扭曲光子的散射，这是由螺旋介质制成的平板，螺旋轴通常与平板平面正常，并且通常在此平面中不变。在特定情况下，螺旋培养基的介电常数张量对应于胆固醇液体晶体，$ C^*$ - 晶状体，双轴性手性nematics and Emectics，$ Q $ - 平板，手性雕刻的薄膜和螺旋型错位。考虑了扰动和非扰动方法。发现光子的散射幅度，概率和Stokes参数的显式表达式考虑了光子波包的形式。选择规则是确定的，表明螺旋培养基将动量和角动量转移到散射的光子上。该特性可用于生产具有总角动量的大投影的扭曲光子。我们描述了转移光子总角动量的投影和信号编码的主要方案的设备。
By using quantum electrodynamics in a dispersive medium, we describe scattering of plane-wave and twisted photons by a slab made of a helical medium, the helix axis being normal to the slab plane and the medium being not translation invariant in this plane, in general. In the particular cases, the permittivity tensor of a helical medium corresponds to cholesteric liquid crystals, $C^*$-smectics, biaxial chiral nematics and smectics, $q$-plates, chiral sculptured thin films, and helical dislocations. Both perturbative and nonperturbative approaches are considered. The explicit expressions for scattering amplitudes, probabilities, and Stokes parameters of photons are found taking into account the form of the photon wave packet. The selection rules are established showing that the helical medium transfers the momentum and the angular momentum to scattered photons. This property can be employed for production of twisted photons with large projection of the total angular momentum. We describe the device for shifting the projection of the total angular momentum of a photon and the principal scheme for signal coding in terms of twisted photons.
