Measuring entangled qutrits and their use for quantum bit commitment.
We produce and holographically measure entangled qudits encoded in transverse spatial modes of single photons. With the novel use of a quantum state tomography method that only requires two-state superpositions, we achieve the most complete characterization of entangled qutrits to date. Ideally, entangled qutrits provide better security than qubits in quantum bit commitment: we model the sensitivity of this to mixture and show experimentally and theoretically that qutrits with even a small amount of decoherence cannot offer increased security over qubits.
Langford
N K
NK
Department of Physics, University of Queensland, Brisbane, QLD 4072, Australia.
Dalton
R B
RB
Harvey
M D
MD
O'Brien
J L
JL
Pryde
G J
GJ
Gilchrist
A
A
Bartlett
S D
SD
White
A G
AG