Zobrazeno 1 - 10
of 362
pro vyhledávání: '"Proctor, T."'
We introduce a general model for a network of quantum sensors, and we use this model to consider the question: when do correlations (quantum or classical) between quantum sensors enhance the precision with which the network can measure an unknown set
Externí odkaz:
http://arxiv.org/abs/1702.04271
Publikováno v:
Phys. Rev. A 94, 062312 (2016)
We consider the problem of estimating multiple phases using a multi-mode interferometer. In this setting we show that while global strategies with multi-mode entanglement can lead to high precision gains, the same precision enhancements can be obtain
Externí odkaz:
http://arxiv.org/abs/1601.05912
Publikováno v:
Phys. Rev. A 93, 033859 (2016)
Quantum metrology exploits quantum correlations to make precise measurements with limited particle numbers. By utilizing inter- and intra- mode correlations in an optical interferometer, we find a state that combines entanglement and squeezing to giv
Externí odkaz:
http://arxiv.org/abs/1505.04011
Autor:
Proctor, T. C., Chudnovsky, E. M.
Publikováno v:
Phys. Rev. B 91, 140201 (2015)
XY and Heisenberg spins, subjected to strong random fields acting at few points in space with concentration $c_r \ll 1$, are studied numerically on 3d lattices containing over four million sites. Glassy behavior with strong dependence on initial cond
Externí odkaz:
http://arxiv.org/abs/1502.06117
Publikováno v:
Phys. Rev. A 90, 033846 (2014)
In optical interferometry multi-mode entanglement is often assumed to be the driving force behind quantum enhanced measurements. Recent work has shown this assumption to be false: single mode quantum states perform just as well as their multi-mode en
Externí odkaz:
http://arxiv.org/abs/1405.7198
Publikováno v:
Phys. Rev. B 88, 224418 (2013)
We study random-field xy spin model at T=0 numerically on lattices of up to 1000 x 1000 x 1000 spins with the accent on the weak random field. Our numerical method is physically equivalent to slow cooling in which the system is gradually losing the e
Externí odkaz:
http://arxiv.org/abs/1311.7211
Publikováno v:
Europhys. Lett. 103, 67009 (2013)
We study vortex states in a 3d random-field XY model of up to one billion lattice spins. Starting with random spin orientations, the sample freezes into the vortex-glass state with a stretched-exponential decay of spin correlations, having short corr
Externí odkaz:
http://arxiv.org/abs/1307.8016
Autor:
Proctor, T. J., Barr, K. E., Hanson, B., Martiel, S., Pavlovic, V., Bullivant, A., Kendon, V. M.
Publikováno v:
Phys. Rev. A 89, 042332 (2014)
We introduce a variation of the discrete time quantum walk, the nonreversal quantum walk, which does not step back onto a position which it has just occupied. This allows us to simulate a dimer and we achieve it by introducing a new type of coin oper
Externí odkaz:
http://arxiv.org/abs/1303.1966
Autor:
Proctor, T. J., Spiller, T. P.
Publikováno v:
Phys. Rev. A 86, 062304 (2012)
We discuss the desired criteria for a two-qubit phase gate and present a method for realising such a gate for quantum computation that is measurement-free and low error. The gate is implemented between qubits via an intermediate bus mode. We take a c
Externí odkaz:
http://arxiv.org/abs/1208.5238
Publikováno v:
Quantum Information & Computation (Rinton Press) Vol. 14, No. 5&6, pp 417-438 2014
We systematically investigated perfect state transfer between antipodal nodes of discrete time quantum walks on variants of the cycles C_4, C_6 and C_8 for three choices of coin operator. Perfect state transfer was found, in general, to be very rare,
Externí odkaz:
http://arxiv.org/abs/1204.5937