Bell-diagonal states

Is there a closed-form formula for the squashed entanglement \(E_{\mathrm{sq}}\) of an arbitrary two-qubit Bell-diagonal state, or a certified approach to determining it numerically?

• Quantum Resource Theory
• Entanglement measures
• Bell-diagonal states

Is the Rains bound asymptotically achievable by completely positive-partial-transpose-preserving (completely PPT-preserving) channels for every full-rank two-qubit Bell-diagonal state, and what channel family achieves it?

• Quantum Resource Theory
• Entanglement distillation
• PPT-preserving operations
• Bell-diagonal states

For every local dimension \(d\geq3\), determine the entanglement of formation of an arbitrary Weyl–Bell-diagonal state.

• Quantum Resource Theory
• Entanglement measures
• Bell-diagonal states

What is the entanglement cost of a qubit Bell-diagonal state for an arbitrary probability vector \(\mathbf p=(p_I,p_X,p_Y,p_Z)\)?

• Quantum Resource Theory
• Entanglement cost
• Bell-diagonal states
• Local operations and classical communication

What is the distillable entanglement \(D(\rho_{\mathbf p})\) under local operations and classical communication (LOCC) for the Bell-diagonal state

• Quantum Resource Theory
• Entanglement distillation
• Bell-diagonal states
• Local operations and classical communication