Fig. 1. OAM of STOV wavepacket with phase singularities embedded in the x–z and y–z domains with vary scaling factors. (a) OAM projection in the y direction and x direction when w_y or w_x is fixed; (b) magnitude of OAM with changing w_x and w_y. The dashed lines correspond to results shown in (a1) and (a2). (c) Orientation of OAM in the x–y plane with varying w_x and w_y.

Fig. 2. OAM of STOV wavepacket with phase singularities embedded in the x–z and x′–z domains. The x′ axis lies in the x–y plane with an offset angle of θ_x−x′ with respect to the x axis. (a) Projection of OAM in the x direction and y direction when θ_x−x′ changes; (b) magnitude of OAM using both the analytical model and the vector model; (c) vectorial representation of the transverse OAM in the x–y plane using two different models.

Fig. 3. Spatiotemporal intensity and phase profile of STOV wavepackets with phase singularities embedded in the x–t and x′–t domains; the angle difference between the x and x′ axes changes from 0 to π in an interval of π/4 (from left to right). (a) Intensity isosurface plot at 15% and 50% of the intensity maximum; (b) phase distribution on the 15% intensity isosurface plot; (c) intensity isosurface plot (15%) in the x–y plane.

Fig. 4. Spatiotemporal intensity and phase profile of STOV wavepackets with phase singularities embedded in the x–z, x′–z, and x–y planes; θ_x−x′ changes from 0 to π in an interval of π/4 (from left to right). (a) Intensity isosurface plot at 5% and 30% of the peak intensity; (b) phase profile on the top of 5% intensity isosurface.