On-chip Quantum Money with Classical Verification

  Adir Hazan [1]  ,  Or Sattah [2]  ,  Alina Karabchevsky [1]  
[1] School of Electrical and Computer Engineering, Ben Gurion University of the Negev, Israel
[2] Computer Science Department, Ben-Gurion University of the Negev, Israel

Due to the fast progress of technology all-over the world, the situation needs to be considered in which counterfeiting is no longer limited by the available technology. The concept of quantum money was first proposed by Wiesner, which is quite similar to the money we use, but it is physically impossible to forge based on the fundamental property of quantum mechanics, the no-cloning theorem.

Recently, quantum money scheme was demonstrated by replacing the challenging quantum verification with a classical channel and a quantum retrieval game, as well as a proof-of-concept attack on this scheme. Such implementation, based on linear optics, is not practical in the real-world applications. Large scale deployment will require chip-based devices for improved performance, miniaturization, and enhanced functionality.

Following the original Wiesner’s protocol, in order to verify the quantum banknotes, here we propose utilizing guided-wave optics to implement an on-chip quantum money protocol relying on classical verification which exploits polarization encoding of weak coherent states of light generated with standard integrated photonics components. Combining our work with state-of-the-art of future quantum memories may pave the way for the major payment method of future global commercial transactions.