Fig. 1. Input field distribution before focusing and planes of observation in the focal region. The field intensity distributions of the right- (|E+|2) and left-handed (|E−|2) circular polarization components in the aperture of the microscope objective are plotted in (a) and (b). The total electric field intensity (|E|2) is shown in (c). All three field intensity distributions are normalized to the maximum value of |E|2. (d) The phase distributions of the right- and left-handed fields (ΦE+ and ΦE−) for different vortex charges m. (e) The focusing scheme. (f) The focal x–y plane is indicated by a gray frame, and the meridional y–z plane is indicated by a red frame.

Fig. 2. Side view (meridional y–z plane) of a VSB with charge number m=1 in the focal region. (a) The total energy density distribution w, (b) the energy density of the electric field wE, and (c) the energy density of the magnetic field wH are normalized to the maximum of w. (d) The magnified phase distribution of the electric x component ΦEx. (e) The black arrowheads indicate the electric orbital LM density poE in the vicinity of the vortex, with the distribution of poEz plotted in the background. The blue color indicates the unusual negative poEz, the red color indicates the positive poEz. The gray circles mark a vortex on the left side and a saddle point on the right side. (f) and (g) represent the electric spin LM density psE and the total LM density p∝poE+psE, with the corresponding z component plotted in the background. All three LM density distributions shown in (e)–(g) are normalized equally.

Fig. 3. Side view of a VSB with charge number m=5 in the focal region. The images in (a–d) are plotted similarly to Figs. 2(a)–2(d).

Fig. 4. Energy and LM in the focal plane. (a) and (b) depict the focal plane of a VSB with charge number m=1. (a) The energy densities w, wE, and wH, are normalized to the maximum value of w. (b) shows the corresponding LM components poz and pz, also normalized to the maximum value of w. The other components px, py, pox, and poy are zero in the focal plane. The black scale bar represents the wavelength λ. (c) and (d) show similar images plotted for a VSB with charge number m=5. (e) The x positions of the centroids of w (blue crosses), poz (red squares), and pz (black stars) are plotted against the charge index m of the VSB.