论文标题
超级踢和光子角和线性动量密度
Superkicks and the photon angular and linear momentum density
论文作者
论文摘要
我们解决了适当定义空间结构电磁场的动量密度的问题。我们表明，当使用规范的能量弹药张量而不是对称的belinfante能量 - 能量量张量时，在局部获得的动量和角动量的表达式并不相同。这对于物质与结构化光的相互作用有重要的后果，例如扭曲的光子。并将为在小测试对象上引起的力和角动量给出截然不同的结果。我们显示了对效应大小的数值估计，在广泛的情况下，规范和对称形式在小物体或原子转子上诱导了非常不同的扭矩或（Superkick）后坐力动量。
We address a problem of proper definition of momentum density for spatially structured electromagnetic fields. We show that the expressions for the momentum and angular momentum obtained locally are not the same when one uses the canonical energy-momentum tensor instead of the symmetric Belinfante energy-momentum tensor in electrodynamics. This has important consequences for interaction of matter with structured light, for example, twisted photons; and would give drastically different results for forces and angular momenta induced on small test objects. We show, with numerical estimates of the size of the effects, situations where the canonical and symmetrized forms induce very different torques or (superkick) recoil momenta on small objects or atomic rotors, over a broad range of circumstances.
