Metamaterials have revolutionized wave physics by enabling unprecedented control over light and sound through tailor-made subwavelength structures. Having explored extraordinary linear phenomena like negative refraction and invisibility, the field is now advancing on two transformative frontiers: nonlinearity and topological physics.
This two-part session is dedicated to the vibrant convergence of these paradigms. We will explore how integrating nonlinear elements (e.g., optical Kerr media, varactors, superconducting circuits) and topological designs into meta-atoms unlocks a new realm of active, tunable, and robust wave-matter interactions. The focus is on moving beyond static properties to achieve dynamic, intensity-dependent, and topologically protected functionalities that are immune to disorder.
We invite contributions on theoretical, computational, and experimental advances, including but not limited to:

• Novel Phenomena at the Intersection: Nonlinear frequency conversion in topological systems, solitons and bistability in topological edge states, nonlinear non-Hermitian topology, generation of topological states via nonlinearity, and harmonic generation in topological metamaterials.
• Advanced Nonlinear & Topological Functionalities: Nonlinearity-induced non-reciprocity (isolators, circulators) with topological robustness, intensity-dependent topological phase transitions, active tuning and reconfiguration of topological waveguides, and nonlinear topological insulators for light and sound.
• Material Platforms & Mechanisms: Topological photonic/phononic crystals with embedded nonlinearity; nonlinear optics in topological plasmonic and dielectric metasurfaces; electronic nonlinearities in RF/microwave topological circuits; optomechanical and superconducting systems for nonlinear topology.
• Emerging Applications & Synergies: Ultrafast topological switching and all-optical logic, protected waveguiding for nonlinear signal processing, robust entangled photon generation, nonlinear imaging and sensing with topological modes, and reconfigurable intelligent surfaces with enhanced robustness.
This session aims to bring together researchers from photonics, acoustics, topological physics, and materials science to foster interdisciplinary discussions, share breakthrough results, and chart the course for future intelligent, adaptive, and robust metamaterial systems.