Resourceefficient generation of linear cluster states by linear optics with postselection
Abstract
Here we report on theoretical research in photonic clusterstate computing. Finding optimal schemes of generating nonclassical photonic states is of critical importance for this field as physically implementable photonphoton entangling operations are currently limited to measurementassisted stochastic transformations. A critical parameter for assessing the efficiency of such transformations is the success probability of a desired measurement outcome. At present there are several experimental groups that are capable of generating multiphoton cluster states carrying more than eight qubits. Separate photonic qubits or small clusters can be fused into a single cluster state by a probabilistic optical CZ gate conditioned on simultaneous detection of all photons with 1/9 success probability for each gate. This design mechanically follows the original theoretical scheme of cluster state generation proposed more than a decade ago by Raussendorf, Browne, and Briegel. The optimality of the destructive CZ gate in application to linear optical cluster state generation has not been analyzed previously. Our results reveal that this method is far from the optimal one. Employing numerical optimization we have identified that the maximal success probability of fusing n unentangled dualrail optical qubits into a linear cluster state is equal to 1/2 ^{n1}; an mtuple of photonic Bell pairmore »
 Authors:
 Brescia Univ., Owensboro, KY (United States); Tulane Univ., New Orleans, LA (United States)
 Air Force Research Lab., Rome, NY (United States). Information Directorate
 Tulane Univ., New Orleans, LA (United States)
 Univ. of Dayton Research Inst., Dayton, OH (United States)
 Air Force Research Lab., Rome, NY (United States). Information Directorate; WrightPatterson Air Force Base, Dayton, OH (United States)
 Air Force Research Lab., Rome, NY (United States). Information Directorate; ; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Publication Date:
 Research Org.:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1185631
 Grant/Contract Number:
 AC0500OR22725; PHY 1005709; FA 87501120218
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Journal of Physics. B, Atomic, Molecular and Optical Physics
 Additional Journal Information:
 Journal Volume: 48; Journal Issue: 4; Journal ID: ISSN 09534075
 Publisher:
 IOP Publishing
 Country of Publication:
 United States
 Language:
 English
 Subject:
 97 MATHEMATICS AND COMPUTING; quantum computer; cluster states; photonic Bell states
Citation Formats
Uskov, D. B., Alsing, P. M., Fanto, M. L., Kaplan, L., Kim, R., Szep, A., and Smith, A. M.. Resourceefficient generation of linear cluster states by linear optics with postselection. United States: N. p., 2015.
Web. doi:10.1088/09534075/48/4/045502.
Uskov, D. B., Alsing, P. M., Fanto, M. L., Kaplan, L., Kim, R., Szep, A., & Smith, A. M.. Resourceefficient generation of linear cluster states by linear optics with postselection. United States. doi:10.1088/09534075/48/4/045502.
Uskov, D. B., Alsing, P. M., Fanto, M. L., Kaplan, L., Kim, R., Szep, A., and Smith, A. M.. 2015.
"Resourceefficient generation of linear cluster states by linear optics with postselection". United States.
doi:10.1088/09534075/48/4/045502. https://www.osti.gov/servlets/purl/1185631.
@article{osti_1185631,
title = {Resourceefficient generation of linear cluster states by linear optics with postselection},
author = {Uskov, D. B. and Alsing, P. M. and Fanto, M. L. and Kaplan, L. and Kim, R. and Szep, A. and Smith, A. M.},
abstractNote = {Here we report on theoretical research in photonic clusterstate computing. Finding optimal schemes of generating nonclassical photonic states is of critical importance for this field as physically implementable photonphoton entangling operations are currently limited to measurementassisted stochastic transformations. A critical parameter for assessing the efficiency of such transformations is the success probability of a desired measurement outcome. At present there are several experimental groups that are capable of generating multiphoton cluster states carrying more than eight qubits. Separate photonic qubits or small clusters can be fused into a single cluster state by a probabilistic optical CZ gate conditioned on simultaneous detection of all photons with 1/9 success probability for each gate. This design mechanically follows the original theoretical scheme of cluster state generation proposed more than a decade ago by Raussendorf, Browne, and Briegel. The optimality of the destructive CZ gate in application to linear optical cluster state generation has not been analyzed previously. Our results reveal that this method is far from the optimal one. Employing numerical optimization we have identified that the maximal success probability of fusing n unentangled dualrail optical qubits into a linear cluster state is equal to 1/2n1; an mtuple of photonic Bell pair states, commonly generated via spontaneous parametric downconversion, can be fused into a single cluster with the maximal success probability of 1/4m1.},
doi = {10.1088/09534075/48/4/045502},
journal = {Journal of Physics. B, Atomic, Molecular and Optical Physics},
number = 4,
volume = 48,
place = {United States},
year = 2015,
month = 1
}
Web of Science

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