Quantum Chaos and Diffusive Transport from Geometric Randomness
How tangled wiring patterns alone can create quantum chaos without disorder
Quantum systems usually need defects or particle interactions to behave chaotically, but this work shows that geometry alone can do it. When quantum particles hop across randomly-wired networks, the shape and connectivity of those networks dictates whether chaos emerges—independent of any material disorder. Large networks generated robust chaos and smooth energy spreading, while thin, highly interconnected ones created a split personality: some particles localized in place while others moved freely.
Quantum chaos and diffusion are central to how quantum systems approach thermal equilibrium—a question with implications for quantum computers, which must avoid chaos to maintain coherence, and for fundamental physics exploring the quantum-to-classical boundary. This finding opens a new knob for controlling these behaviors without engineering material defects, potentially useful for designing quantum devices where geometry is easier to control than atomic-scale disorder.