Entanglement concentration with quantum nondemolition Hamiltonians
Abstract
We devise and examine two procrustean entanglement concentration schemes using quantum nondemolition (QND) interaction Hamiltonians in the continuous variable regime, applicable for light, for atomic ensembles or in a hybrid setting. We thus expand the standard entanglement distillation toolbox for use of a much more general, versatile, and experimentally feasible interaction class. The first protocol uses Gaussian ancillary modes and a non-Gaussian postmeasurement, the second a non-Gaussian ancillary mode and a Gaussian postmeasurement. We explicitly calculate the density matrix elements of the non-Gaussian mixed states resulting from these protocols using an elegant Wigner-function-based method in a numerically efficient manner. We then quantify the entanglement increase calculating the logarithmic negativity of the output state and discuss and compare the performance of the protocols.
Citation
Tatham , R & Korolkova , N 2014 , ' Entanglement concentration with quantum nondemolition Hamiltonians ' , Physical Review. A, Atomic, molecular, and optical physics , vol. 89 , no. 1 , 012308 . https://doi.org/10.1103/PhysRevA.89.012308
Publication
Physical Review. A, Atomic, molecular, and optical physics
Status
Peer reviewed
ISSN
1050-2947Type
Journal article
Description
We also acknowledge an EU grant under the FET-Open project COMPAS (No. 212008) and are grateful for the support of the Scottish Universities Physics Alliance (SUPA).Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.