Shigenari Suzuki

Ultra-large-scale continuous-variable cluster states multiplexed in the time domain

A continuous-variable cluster state containing more than 10,000 entangled modes is deterministically generated and fully characterized. The developed time-domain multiplexing method allows each quantum mode to be manipulated by the same optical components at different times. An efficient scheme for measurement-based quantum computation on this cluster state is presented.

Generation of Large-Amplitude Coherent-State Superposition via Ancilla-Assisted Photon Subtraction

We propose and demonstrate a novel method to generate a large-amplitude coherent-state superposition (CSS) via ancilla-assisted photon subtraction. The ancillary mode induces quantum interference of indistinguishable processes in an extended space, widening the controllability of quantum superposition at the conditional output. We demonstrate this by a simple time-separated two-photon subtraction from continuous wave squeezed light. We observe the largest CSS of traveling light ever reported without correcting any imperfections, which will enable various quantum information applications with CSS states.

Multimode theory of measurement-induced non-Gaussian operation on wideband squeezed light : Analytical formula

We present a multimode theory of non-Gaussian operation induced by an imperfect on/off-type photon detector on a splitted beam from a wideband squeezed light. The events are defined for finite time duration

Practical purification scheme for decohered coherent-state superpositions via partial homodyne detection

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NON-GAUSSIAN CONTROL OF CONTINUOUS VARIABLES WITH PHOTON COUNTING AND FILTERING

in the time domain. The non-Gaussian output state is measured by the homodyne detector with finite bandwidh

Photon subtraction and single photon squeezing schemes for generation of Schrodinger cat-like states under experimental imperfections

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Quantum Nondemolition Gate Operations and Measurements in Real Time on Fluctuating Signals

. Under this time- and band-limitation to the quantm states, we develop a formalism to evaluate the frequency mode matching between the on/off trigger channel and the conditional signal beam in the homodyne channel. Our formalism is applied to the CW and pulsed schemes. We explicitly calculate the Wigner function of the conditional non-Gaussian output state in a realistic situation. Good mode matching is achieved for

Demonstration of Real-Time Quantum Non-Demolition Interaction

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Generation of 1.5 µm Squeezed Vacuum Pulse Using a Sagnac Loop Interferometer

, where the discreteness of modes becomes prominant, and only a few modes become dominant both in the on/off and the homodyne channels. If the trigger beam is projected nearly onto the single photon state in the most dominant mode in this regime, the most striking non-classical effect will be observed in the homodyne statistics. The increase of

Generation of Quadrature Squeezed State of Light with High Squeezing Level and High Purity

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