0000000000739721

AUTHOR

Shota Yokoyama

0000-0001-6708-3785

showing 3 related works from this author

Optical quantum information processing and storage

2018

Here we report our recent experimental progresses in optical quantum information processing. In particular, the following topics are included. First, we extend the heralding scheme to multi-mode states and demonstrate heralded creation of qutrit states. Next, we demonstrate storage of single-photon states and synchronized release of them. Then, we demonstrate real-time acquisition of quadrature values of heralded states by making use of an exponentially rising shape of wave-packets. Finally, we demonstrate cluster states in an arbitrarily long chain in the longitudinal direction.

010309 opticsQuantum opticsPhysics0103 physical sciencesStatistical physicsQuantum entanglementQutrit010306 general physicsQuantum information processing01 natural sciencesLong chainQuadrature (astronomy)Longitudinal directionQuantum Communications and Quantum Imaging XVI
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Demonstration of a fully tuneable entangling gate for continuous-variable one-way quantum computation

2015

We introduce a fully tuneable entangling gate for continuous-variable one-way quantum computation. We present a proof-of-principle demonstration by propagating two independent optical inputs through a three-mode linear cluster state and applying the gate in various regimes. The genuine quantum nature of the gate is confirmed by verifying the entanglement strength in the output state. Our protocol can be readily incorporated into efficient multi-mode interaction operations in the context of large-scale one-way quantum computation, as our tuning process is the generalisation of cluster state shaping.

PhysicsQuantum PhysicsTheoryofComputation_GENERALNonlinear opticsFOS: Physical sciencesAtomic and Molecular Physics and OpticsContinuous variableQuantum circuitQuantum gateControlled NOT gateQuantum mechanicsQuantum algorithmQuantum Physics (quant-ph)Quantum computer
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Quantum Nondemolition Gate Operations and Measurements in Real Time on Fluctuating Signals

2017

We demonstrate an optical quantum nondemolition (QND) interaction gate with a bandwidth of about 100 MHz. Employing this gate, we are able to perform QND measurements in real time on randomly fluctuating signals. Our QND gate relies on linear optics and offline-prepared squeezed states. In contrast to previous demonstrations on narrow sideband modes, our gate is compatible with quantum states temporally localized in a wave-packet mode including non-Gaussian quantum states. This is the cornerstone of realizing quantum error correction and universal gate operations.

PhysicsQuantum PhysicsSidebandBandwidth (signal processing)FOS: Physical sciencesQuantum Physics01 natural sciences010309 opticsLinear opticsComputer Science::Hardware ArchitectureComputer Science::Emerging TechnologiesQuantum error correctionQuantum stateQuantum mechanics0103 physical sciencesHardware_INTEGRATEDCIRCUITS010306 general physicsQuantum Physics (quant-ph)Quantum
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