Vortex solitons in topological disclination lattices.

Area of Science:

• Nonlinear optics
• Condensed matter physics
• Topological photonics

Background:

• Higher-order topological insulators exhibit unique boundary phenomena.
• Disclination lattices provide a platform for realizing topological states.
• Vortex solitons are self-trapped light beams with topological properties.

Purpose of the Study:

• To report the existence of thresholdless vortex solitons in disclination lattices.
• To investigate the interplay between nonlinearity and higher-order topology.
• To explore the control of vortex soliton properties via power.

Main Methods:

• Theoretical analysis of vortex soliton formation in disclination lattices.
• Numerical simulations to confirm soliton stability and localization.
• Investigation of the bifurcation from linear topological states.

Main Results:

• Thresholdless vortex solitons are found trapped at the core of disclination lattices.
• Vortex state bifurcation from linear topological counterparts is demonstrated.
• Soliton localization and propagation constant are controllable by power.
• Topological nature ensures strong field confinement and enhanced stability.
• Discrete rotational symmetry restricts the maximum topological charge.

Conclusions:

• Topologically nontrivial structures strongly stabilize excited soliton states.
• This work opens new avenues for soliton-based applications in topological photonics.