Stability and adaptive evolution of higher-order vector vortex solitons in thermally nonlinear media with tunable transverse size

The stability of a higher-order vector vortex (HVV) soliton, comprised of a fundamental-mode beam incoherently coupling with a higher-order vortex beam, is investigated in a thermally nonlocal nonlinear medium. By linear stability analysis, we find the broad and stable interval for HVV solitons and the monotonically increasing relation between the stable interval and the vortical topological charge. The adaptive evolution of this stable HVV soliton in the longitudinally-inhomogeneous medium with tunable transverse size is also discussed. The smooth transition and controllable propagation of HVV solitons, and the oscillating behaviour of HVV breathers under different nonlocal potentials are investigated. In addition, the instability suppression of the HVV soliton by means of gradual change of transverse size is also found.