Bell-GHZ Measurement-Device-Independent Quantum Key Distribution

In this work, a one-sided measurement-device-independent quantum key distribution protocol that uses Bell and Greenberger–Horne–Zeilinger (GHZ) states is proposed. The protocol considers three parties: Alice and Bob, who will share the key at the end of the protocol; and Charlie, who plays the role of facilitating the key distribution without having access to the key itself. Alice and Charlie are trusted users, while Bob is uncharacterized. The protocol is asymmetrical, meaning that Alice sends one qubit while Bob sends two; this allows Bob to identify himself via a previously assigned ID; if this authentication fails, the key distribution also will.