8 research outputs found
Measuring the Mermin-Peres magic square using an online quantum computer
We have implemented the six series of three commuting measurement of the
Mermin-Peres magic square on an online, five qubit, quantum computer. The magic
square tests if the measurements of the system can be described by physical
realism (in the EPR sense) and simultaneously are non-contextual. We find that
our measurement results violate any realistic and non-contextual model by
almost 28 standard deviations. We also find that although the quantum computer
we used for the measurements leaves much to be desired in producing accurate
and reproducible results, the simplicity, the ease of re-running the
measurement programs, and the user friendliness compensates for this fact.Comment: 7 pages, 2 figures, 5 table
Generation of picosecond pulsed coherent state superpositions
We present the generation of approximated coherent state superpositions -
referred to as Schr\"odinger cat states - by the process of subtracting single
photons from picosecond pulsed squeezed states of light at 830 nm. The squeezed
vacuum states are produced by spontaneous parametric down-conversion (SPDC) in
a periodically poled KTiOPO4 crystal while the single photons are
probabilistically subtracted using a beamsplitter and a single photon detector.
The resulting states are fully characterized with time-resolved homodyne
quantum state tomography. Varying the pump power of the SPDC, we generated
different states which exhibit non-Gaussian behavior.Comment: 17 pages, 8 figures, 3 table