Coaxial Self-Trapping of White and Gray Regions of an Incandescent Field: A Bright Core with a Dark Cladding

Figure 2

2D and 3D spatial intensity profiles of the gray ring-embedded beam at 𝑧 = 0.0 mm and (b–f) its evolution at 𝑧 = 6.0 mm. For clarity, both top-down and bottom-up perspectives of 3D profiles are included. In (a), the scale bar = 250 μm and applies to (b–h). The spectral colour scale corresponds to relative intensities of 0% (blue) to 100% (red) and is the same in (a–g); for clarity, the scale was magnified by approximately ×2 in (g). Intensities and widths of the ring and core are indicated.