Quantum tomographic cryptography with Bell diagonal states: non-equivalence of classical and quantum distillation protocols

Abstract

We present a generalized tomographic quantum key distribution protocol in which the two parties share a Bell diagonal mixed state of two qubits. We show that if an eavesdropper performs a coherent measurement on many quantum ancilla states simultaneously, classical methods of secure key distillation are less effective than quantum entanglement distillation protocols. We also show that certain Bell diagonal states are resistant to any attempt of incoherent eavesdropping.

9 pages. 2 figures There was an error in the formula 4 (transformation of Bell states). This error does not change the main result of the paper, namely, that quantum distillation is more powerful than classical advantage distillation

References in corpus (6)

• Mixed State Entanglement and Quantum Error Correction
• Separability Criterion for Density Matrices
• Quantum State Discrimination
• Tomographic Quantum Cryptography
• Equivalence between two-qubit entanglement and secure key distribution
• Tomographic Quantum Cryptography: Equivalence of Quantum and Classical Key Distillation

Cited by in corpus (7)

• Tomography increases key rates of quantum-key-distribution protocols
• Experimental Entanglement Distillation of Two-qubit Mixed States Under Local filtering Operations
• Generation of Bell and GHZ states from a hybrid qubit-photon-magnon system
• Secrecy content of two-qubit states
• Coherent Eavesdropping Attacks in Quantum Cryptography: Nonequivalence of Quantum and Classical Key Distillation
• A Study of Channel Estimation and Postprocessing in Quantum Key Distribution Protocols
• Quantum Tomographic Cryptography with a Semiconductor Single Photon Source