Year: 2026
Type: preprint
Abstract: Entanglement among particles distinguishes correlated quantum materials from conventional metals and semiconductors. Experimentally certifying intrinsic entanglement among interacting electrons in materials is important not only for classifying states of matter, but also for developing material-based quantum technologies. Here, we introduce a transport protocol for witnessing multipartite entanglement from the equilibrium current-noise spectrum, measured directly or reconstructed from optical conductivity. The appropriately integrated, symmetrized, and projected noise spectrum obeys an upper bound derived from microscopic model parameters. Unlike witnesses based on localized spins, our framework applies to general electronic states without requiring magnetic moments and remains invariant under single-particle basis transformations. We benchmark it in twisted bilayer graphene, twisted bilayer MoTe$_2$, and Hubbard models, and demonstrate entanglement certification in a fractional Chern insulator. This approach extends recently developed scattering-based entanglement witnesses to ultralow-temperature conditions, where many candidate entangled phases emerge.
Source: arXiv (Cornell University)
Institution: Emory University
Language: English
Topic: Quantum many-body systems
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7203700558