Spatiotemporal flux breathing and topological sculpting in structured transverse orbital angular momentum lattices.

Spatiotemporal optical vortices (STOVs) carrying transverse orbital angular momentum (OAM) fundamentally expand light-structuring capabilities. However, current rigid-body generation paradigms constrain transverse OAM to a single scalar property, leaving rich internal wavepacket dynamics inaccessible. This rigidity contrasts with ubiquitous natural vortices where symmetry breaking is the norm. Here, we break rotational symmetry via the nonlinear mapping of the azimuthal phase gradient, realizing programmable spatiotemporal flux breathing. We theoretically and experimentally demonstrate that local phase gradient variations induce instantaneous group velocity anisotropy. This compels local OAM density to spontaneously reorganize into stable, multilobed lattice structures while strictly preserving global topological charge. Furthermore, we harness these structures' modulation frequency for free-space information transfer, achieving high-fidelity encoding and decoding of spatiotemporal topological states. This work transitions STOVs from passive scalar objects to structured functional carriers, opening avenues for high-dimensional optical communications, ultrafast spatiotemporal manipulation, strong-field physics, and high-dimensional quantum entanglement.