论文标题
光学，声学和量子机械时空涡旋脉冲的轨道角动量
Orbital angular momentum of optical, acoustic, and quantum-mechanical spatiotemporal vortex pulses
论文作者
论文摘要
由于最近在光时空涡流脉冲（STVP）产生的过程中，有一个理论上的讨论，讨论了这种脉冲携带的横向轨道角动量（OAM）。最近的两幅作品[K. Y. Bliokh，物理。莱特牧师。 126，243601（2021）]和[S. W. Hancock等人，物理。莱特牧师。 127，193901（2021）]声称圆形STVP的OAM值差异为2。在这里，我们通过证明Hancock等人的结果来解决这一争议。对于总绿色的绿色状况是正确的，而Bliokh的结果描述了适当定义的OAM内在部分。 OAM的另一个外部部分源于以下事实：相同振幅的平面波，但脉冲光谱中的不同频率包含不同的光子，即使在STVP中，光子质心的横向涡流依赖性移位也诱导了对称能量密度分布。我们描述了声学和量子偏见的类似特征（Klein-Gordon和Nutary Spin）STVP。在所有情况下，只有固有的OAM才能保持通用形式与问题的细节无关，并且类似于单色涡流梁的OAM。
Motivated by recent progress in the generation of optical spatiotemporal vortex pulses (STVPs), there is a theoretical discussion about the transverse orbital angular momentum (OAM) carried by such pulses. Two recent works [K. Y. Bliokh, Phys. Rev. Lett. 126, 243601 (2021)] and [S. W. Hancock et al., Phys. Rev. Lett. 127, 193901 (2021)] claimed the OAM values which differ by a factor of 2 for circular STVPs. Here we resolve this controversy by showing that the result by Hancock et al. is correct for the total OAM, while the result by Bliokh describes the suitably defined intrinsic part of the OAM. The other, extrinsic part of the OAM originates from the fact that plane waves of the same amplitude but different frequencies in the pulse spectrum contain different densities of photons, which induces a transverse vortex-dependent shift of the photon centroid even in a STVP with symmetric energy-density distribution. We describe similar peculiarities of acoustic and quantum-relativistic (Klein-Gordon and arbitrary-spin) STVPs. In all cases, only the intrinsic OAM keeps a universal form independent of the details of the problem and similar to the OAM of monochromatic vortex beams.
