821 citations · 919 across the 4 of their papers we have counts for
6 papers
Beating the standard quantum limit: Phase super-sensitivity of N-photon interferometers
Ryo Okamoto, Holger F. Hofmann, Tomohisa Nagata +3
Quantum metrology promises greater sensitivity for optical phase measurements than could ever be achieved classically. Here we present a theory of the phase sensitivity for the gen…
Beating the Standard Quantum Limit with Four Entangled Photons
Tomohisa Nagata, Ryo Okamoto, Jeremy L. O'Brien +2
Precision measurements are important across all fields of science. In particular, optical phase measurements can be used to measure distance, position, displacement, acceleration a…
Characterization of a noisy quantum process by complementary classical operations
Holger F. Hofmann, Ryo Okamoto, Shigeki Takeuchi
One of the challenges in quantum information is the demonstration of quantum coherence in the operations of experimental devices. While full quantum process tomography can do the j…
Analysis of an experimental quantum logic gate by complementary classical operations
Holger F. Hofmann, Ryo Okamoto, Shigeki Takeuchi
Quantum logic gates can perform calculations much more efficiently than their classical counterparts. However, the level of control needed to obtain a reliable quantum operation is…
Demonstration of an optical quantum controlled-NOT gate without path interference
Ryo Okamoto, Holger F. Hofmann, Shigeki Takeuchi +1
We report the first experimental demonstration of an optical quantum controlled-NOT gate without any path interference, where the two interacting path interferometers of the origin…
A high-yield single photon source using gated spontaneous parametric down conversion
Shigeki Takeuchi, Ryo Okamoto, Keiji Sasaki
The construction of a single photon source using gated parametric fluorescence is reported with the measurement results of the photon number distribution. A beamlike twin-photon me…