Search Results - "RALPH, T. C"

Boson sampling from a Gaussian state by Lund, A P, Laing, A, Rahimi-Keshari, S, Rudolph, T, O'Brien, J L, Ralph, T C

“…We pose a randomized boson-sampling problem. Strong evidence exists that such a problem becomes intractable on a classical computer as a function of the number…”
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Quantum sampling problems, BosonSampling and quantum supremacy by Lund, A. P., Bremner, Michael J., Ralph, T. C.

“…There is a large body of evidence for the potential of greater computational power using information carriers that are quantum mechanical over those governed…”
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Heralded noiseless linear amplification and distillation of entanglement by Pryde, G. J, Xiang, G. Y, Ralph, T. C, Lund, A. P, Walk, N

“…Signal amplification is ubiquitous in the control of physical systems, and the ultimate performance limit of amplifiers is set by quantum physics. Increasing…”
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Entanglement decoherence in a gravitational well according to the event formalism by Ralph, T C, Pienaar, J

“…The event formalism is a nonlinear extension of quantum field theory designed to be compatible with the closed time-like curves that appear in general…”
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Demonstration of an all-optical quantum controlled-NOT gate by O'Brien, J. L, Pryde, G. J, White, A. G, Ralph, T. C, Branning, D

“…The promise of tremendous computational power, coupled with the development of robust error-correcting schemes, has fuelled extensive efforts to build a…”
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Quantum key distribution without sending a quantum signal by Ralph, T C, Walk, N

“…Quantum Key Distribution is a quantum communication technique in which random numbers are encoded on quantum systems, usually photons, and sent from one party,…”
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Tomography of quantum detectors by Lundeen, J. S, Walmsley, I. A, Feito, A, Coldenstrodt-Ronge, H, Pregnell, K. L, Silberhorn, Ch, Ralph, T. C, Eisert, J, Plenio, M. B

“…Measurement connects the world of quantum phenomena to the world of classical events. It has both a passive role-in observing quantum systems-and an active…”
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Photon sorting, efficient bell measurements, and a deterministic controlled-Z gate using a passive two-level nonlinearity by Ralph, T C, Söllner, I, Mahmoodian, S, White, A G, Lodahl, P

“…Although the strengths of optical nonlinearities available experimentally have been rapidly increasing in recent years, significant challenges remain to using…”
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Quantum process tomography of a controlled-not gate by O'BRIEN, J. L, PRYDE, G. J, GILCHRIST, A, JAMES, D. F. V, LANGFORD, N. K, RALPH, T. C, WHITE, A. G

“…We demonstrate complete characterization of a two-qubit entangling process--a linear optics controlled-NOT gate operating with coincident detection--by quantum…”
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Measurement of quantum weak values of photon polarization by PRYDE, G. J, O'BRIEN, J. L, WHITE, A. G, RALPH, T. C, WISEMAN, H. M

“…We experimentally determine weak values for a single photon's polarization, obtained via a weak measurement that employs a two-photon entangling operation, and…”
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Loss-tolerant optical qubits by RALPH, T. C, HAYES, A. J. F, GILCHRIST, Alexei

“…We present a linear optics quantum computation scheme that employs a new encoding approach that incrementally adds qubits and is tolerant to photon loss…”
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Configurable unitary transformations and linear logic gates using quantum memories by Campbell, G T, Pinel, O, Hosseini, M, Ralph, T C, Buchler, B C, Lam, P K

“…We show that a set of optical memories can act as a configurable linear optical network operating on frequency-multiplexed optical states. Our protocol is…”
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Arbitrary multi-qubit generation by Shahandeh, F, Lund, A P, Ralph, T C, Vanner, M R

“…We propose and analyse a scheme for single-rail-encoded arbitrary multi-qubit quantum-state generation to provide a versatile tool for quantum optics and…”
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On the problem of non-zero word error rates for fixed-rate error correction codes in continuous variable quantum key distribution by Johnson, Sarah J, Lance, Andrew M, Ong, Lawrence, Shirvanimoghaddam, Mahyar, Ralph, T C, Symul, Thomas

“…The maximum operational range of continuous variable quantum key distribution protocols has shown to be improved by employing high-efficiency forward error…”
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Continuous variable quantum cryptography: beating the 3 dB loss limit by Silberhorn, Ch, Ralph, T C, Lütkenhaus, N, Leuchs, G

“…We demonstrate that secure quantum key distribution systems based on continuous variable implementations can operate beyond the apparent 3 dB loss limit that…”
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Experimental investigation of criteria for continuous variable entanglement by Bowen, W P, Schnabel, R, Lam, P K, Ralph, T C

“…We generate a pair of entangled beams from the interference of two amplitude squeezed beams. The entanglement is quantified in terms of EPR paradox and…”
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Fault-tolerant linear optical quantum computing with small-amplitude coherent States by Lund, A P, Ralph, T C, Haselgrove, H L

“…Quantum computing using two coherent states as a qubit basis is a proposed alternative architecture with lower overheads but has been questioned as a practical…”
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Measuring a photonic qubit without destroying it by Pryde, G J, O'Brien, J L, White, A G, Bartlett, S D, Ralph, T C

“…Measuring the polarization of a single photon typically results in its destruction. We propose, demonstrate, and completely characterize a quantum…”
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Heralded noiseless amplification of a photon polarization qubit by Kocsis, S., Xiang, G. Y., Ralph, T. C., Pryde, G. J.

“…Long-distance quantum communication is limited by optical absorption and scattering. A noiseless amplifier for photonic qubits coherently encoded across two…”
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Optimized generation of heralded Fock states using parametric down-conversion by Brańczyk, Agata M, Ralph, T C, Helwig, Wolfram, Silberhorn, Christine

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