Quantifying how much quantum information can be eavesdropped (Vol. 50, No. 2)

Eavesdropping. Credit: Photo by Dmitry Ratushny on Unsplash

New study yields more precise characterisation of monogamous and polygamous entanglement of quantum information units

Encrypted communication is achieved by sending quantum information in basic units called quantum bits, or qubits. The most basic type of quantum information processing is quantum entanglement. However, this process remains poorly understood. Better controlling quantum entanglement could help to improve quantum teleportation, the development of quantum computers, and quantum cryptography. Now, the authors have focused on finding ways to enhance the reliability of quantum secret sharing. In a new study published recently, they provide a much finer characterisation of the distributions of entanglement in multi-qubit systems than previously available. In the context of quantum cryptography, these findings can be used to estimate the quantity of information an eavesdropper can capture regarding the secret encryption key.

Z. Zhang, Y. Luo, and Y. Li , Tighter monogamy and polygamy relations in multiqubit systems, Eur. Phys. J. D 73, 13 (2019)