AI 中文总结
研究铷蒸汽在超精细帕邢 - 巴克区域的旋光性效应，以方位角偏振输入光束为例，揭示低原子密度下圆双折射主导，高蒸汽温度时二色性更重要，其导致偏振取向和椭圆率复杂变化。
AI 中文摘要
在原子共振线附近的轴向磁场中，原子样品的圆双折射可产生大的法拉第旋转。法拉第角是磁场强度、可通过改变原子气体温度来改变的原子样品光密度以及与跃迁频率的光学失谐的函数。更一般地，原子样品中的磁光效应除双折射外还包括圆二色性，导致椭圆率和偏振取向的改变。通常此类效应是针对均匀线性偏振进行研究的，但这些机制也适用于诸如矢量涡旋等偏振结构。我们以方位角偏振输入光束为例，研究了铷蒸汽在超精细帕邢 - 巴克区域的旋光性效应。我们表明，对于低原子密度，圆双折射比二色性占主导，方位角偏振朝径向偏振旋转，旋转角随光密度增加而增大。在高蒸汽温度下，二色性变得越来越重要，导致取向和椭圆率都出现复杂变化。
英文摘要
Large Faraday rotations can be generated by circular birefringence of atomic samples in an axial magnetic field in the vicinity of atomic resonance lines. The Faraday angle is a function of the magnetic field strength, the optical density of the atomic sample which may be varied by changing the temperature of the atomic gas, and of course the optical detuning from the transition frequencies. More generally, magneto-optical effects in atomic samples include circular dichroism in addition to birefringence, resulting in a modification of the ellipticity as well as the polarisation alignment. Usually such effects are investigated for homogeneous linear polarisations, but the mechanisms apply also to polarisation structures such as vector vortices. We investigate the effect of optical activity of a rubidium vapour in the Hyperfine Paschen-Back regime, for the example of an azimuthally polarised input light beam. We show that for low atomic densities, circular birefringence dominates over dichroism, and azimuthal polarisation is rotated towards radial polarisation. The rotation angle increases with increasing optical densities. At high vapour temperatures, dichroism becomes more and more relevant, leading to intricate variations of both alignment and ellipticity.
Comments6 pages, 5 figures, submitted to JOSAB
