Tomography of a displacement photon counter for discrimination of single-rail optical qubits

Shuro Izumi*, Jonas Schou Neergaard-Nielsen, Ulrik Lund Andersen

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

203 Downloads (Pure)


We investigate the performance of a detection strategy composed of a displacement operation and a photon counter, which is known as a beneficial tool in optical coherent communications, to the quantum state discrimination of the two superpositions of vacuum and single photon states corresponding to the eigenstates in the single-rail encoding of photonic qubits. We experimentally characterize the detection strategy in vacuum-single photon two-dimensional space using quantum detector tomography and evaluate the achievable discrimination error probability from the reconstructed measurement operators. We furthermore derive the minimum error rate obtainable with Gaussian transformations and homodyne detection. Our proof-of-principle experiment shows that the proposed scheme can achieve a discrimination error surpassing homodyne detection.
Original languageEnglish
Article number085502
JournalJournal of Physics B: Atomic, Molecular and Optical Physics
Issue number8
Number of pages5
Publication statusPublished - 2018


Dive into the research topics of 'Tomography of a displacement photon counter for discrimination of single-rail optical qubits'. Together they form a unique fingerprint.

Cite this