论文标题
径向极化的扭曲光的光学特性
Optical properties of radially-polarised twisted light
论文作者
论文摘要
我们表明，通常，任何类型的径向极化的偏离式扭曲的光学模式仅带有轴向总的光学角动量（am）$ {\ bar {\ cal j} _z} = \ ell {\ ell {\ cal l} _0 $，$ \ ell $ eell $是绕组编号和$ {\ cal l} _0 $ a}但是，该模式显示为零旋转角动量（SAM），因此仅具有轨道角动量（OAM），而没有SAM。发现螺旋度与$ \ ell $成正比，因此径向极化模式显示手性。当应用于Laguerre-Gaussian（LG）模式时，我们的治疗导致总螺旋度等于$（\ ell/| \ ell |）{\ cal Q} $，其中$ {\ cal Q} $是动作常数。因子$（\ ell/| \ ell |）= \ pm 1 $，取决于符号，而不是$ \ ell $的幅度，因此对于任何径向极偏置的LG模式而言，结果都保留，但是其绕组数$ \ ell $的幅度很大。动作常数$ {\ cal Q} $的大小，因此，对于所有此类大型大型腰部的LG模式$ W_0 $。
We show that, in general, any type of radially-polarised paraxial twisted optical mode carries only an axial total optical angular momentum (AM) ${\bar {\cal J}_z}=\ell{\cal L}_0$ where $\ell$ is the winding number and ${\cal L}_0$ is a constant. This mode, however, is shown to have zero spin angular momentum (SAM), so it is endowed only with orbital angular momentum (OAM) and no SAM. The helicity is found to be proportional to $\ell$, hence radially-polarised modes display chirality. When applied to a Laguerre-Gaussian (LG) mode our treatment leads to a total helicity equal to $(\ell/|\ell|){\cal Q}$, where ${\cal Q}$ is the action constant. The factor $(\ell/|\ell|)=\pm 1$, depends on the sign, not the magnitude of $\ell$ and so the result holds for any radially-polarised LG mode however large the magnitude of its winding number $\ell$ is. The magnitude of the action constant ${\cal Q}$ and hence the helicity are diminished for all such LG modes of large beam waist $w_0$.
