A team of quantum physicists have presented what they claim is the beginning of counterfeit-proof “quantum money.”
Using an image encoded in the polarization states of single photons, researchers experimentally confirmed it’s possible to create a banknote that’s unable to be replicated. Researchers said this is because “unknown quantum information cannot be perfectly copied.”
Authors of the report, entitled “Experimental quantum forgery of quantum optical money,” include Karol Bartkiewicz; Antonín Černoch; Grzegorz Chimczak; Karel Lemr; Adam Miranowicz; and Franco Nori.
“We demonstrate that it is possible to use quantum states to prepare a banknote that cannot be ideally copied without making the owner aware of unauthorized actions,” state the researchers. “We provide the security conditions for quantum money by investigating the physically-achievable limits on the fidelity of 1-to-2 copying of arbitrary sequences of qubits. These results can be applied as a security measure in quantum digital rights management.”
Quantum money was originally proposed in the 1970s by U.S. physicist Stephen Wiesner, who argued quantum physics could be used to produce counterfeit-proof banknotes. It was widely rejected and remained unpublished until 1983.