Bell states, as maximally entangled two-qubit states, are indispensable to the foundational and applied aspects of quantum information science. Defined mathematically as:

∣Φ±⟩=12(∣00⟩±∣11⟩),∣Ψ±⟩=12(∣01⟩±∣10⟩),|\Phi^{\pm}\rangle = \frac{1}{\sqrt{2}} \left( |00\rangle \pm |11\rangle \right), \quad |\Psi^{\pm}\rangle = \frac{1}{\sqrt{2}} \left( |01\rangle \pm |10\rangle \right),∣Φ±⟩=2​1​(∣00⟩±∣11⟩),∣Ψ±⟩=2​1​(∣01⟩±∣10⟩),

these states are central to quantum protocols due to their unique properties. Some particularly advanced areas where Bell states are being utilized include:

Discussion Points:

• Are there any new methods for generating high-fidelity Bell states at scale in quantum hardware platforms?
• How do decoherence and noise specifically affect Bell-state fidelity, and what mitigation techniques show the most promise?
• What are the theoretical and practical implications of extending Bell-state concepts to multi-qubit entangled states or graph states?

I’d love to hear from researchers working on theoretical models, experimental implementations, or technological innovations related to Bell states. Let’s explore how these remarkable states continue to push the boundaries of quantum science.

Citation To file: 10.1038/s41534-021-00499-8