1 research outputs found
Entanglement-secured single-qubit quantum secret-sharing
In single-qubit quantum secret sharing, a secret is shared between N parties
via manipulation and measurement of one qubit at a time. Each qubit is sent to
all N parties in sequence; the secret is encoded in the first participant's
preparation of the qubit state and the subsequent participants' choices of
state rotation or measurement basis. We present a protocol for single-qubit
quantum secret sharing using polarization entanglement of photon pairs produced
in type-I spontaneous parametric downconversion. We investigate the protocol's
security against eavesdropping attack under common experimental conditions: a
lossy channel for photon transmission, and imperfect preparation of the initial
qubit state. A protocol which exploits entanglement between photons, rather
than simply polarization correlation, is more robustly secure. We implement the
entanglement-based secret-sharing protocol with 87% secret-sharing fidelity,
limited by the purity of the entangled state produced by our present apparatus.
We demonstrate a photon-number splitting eavesdropping attack, which achieves
no success against the entanglement-based protocol while showing the predicted
rate of success against a correlation-based protocol.Comment: 10 pages, 8 figure