Repeatuntilsuccess cubic phase gate for universal continuousvariable quantum computation
Abstract
We report that to achieve universal quantum computation using continuous variables, one needs to jump out of the set of Gaussian operations and have a nonGaussian element, such as the cubic phase gate. However, such a gate is currently very difficult to implement in practice. Here we introduce an experimentally viable “repeatuntilsuccess” approach to generating the cubic phase gate, which is achieved using sequential photon subtractions and Gaussian operations. Ultimately, we find that our scheme offers benefits in terms of the expected time until success, as well as the fact that we do not require any complex offline resource state, although we require a primitive quantum memory.
 Authors:
 Univ. of Toronto, ON (Canada). Dept. of Physics
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Quantum Information Science Group; Univ. of Tennessee, Knoxville, TN (United States). Dept. of Physics and Astronomy
 Univ. of Tennessee, Knoxville, TN (United States). Dept. of Physics and Astronomy
 QKD Corp., Toronto, ON (Canada)
 Publication Date:
 Research Org.:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1185866
 Alternate Identifier(s):
 OSTI ID: 1179951
 Grant/Contract Number:
 AC0500OR22725
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Physical Review. A
 Additional Journal Information:
 Journal Volume: 91; Journal Issue: 3; Journal ID: ISSN 10502947
 Publisher:
 American Physical Society (APS)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 97 MATHEMATICS AND COMPUTING
Citation Formats
Marshall, Kevin, Pooser, Raphael, Siopsis, George, and Weedbrook, Christian. Repeatuntilsuccess cubic phase gate for universal continuousvariable quantum computation. United States: N. p., 2015.
Web. doi:10.1103/PhysRevA.91.032321.
Marshall, Kevin, Pooser, Raphael, Siopsis, George, & Weedbrook, Christian. Repeatuntilsuccess cubic phase gate for universal continuousvariable quantum computation. United States. doi:10.1103/PhysRevA.91.032321.
Marshall, Kevin, Pooser, Raphael, Siopsis, George, and Weedbrook, Christian. 2015.
"Repeatuntilsuccess cubic phase gate for universal continuousvariable quantum computation". United States.
doi:10.1103/PhysRevA.91.032321. https://www.osti.gov/servlets/purl/1185866.
@article{osti_1185866,
title = {Repeatuntilsuccess cubic phase gate for universal continuousvariable quantum computation},
author = {Marshall, Kevin and Pooser, Raphael and Siopsis, George and Weedbrook, Christian},
abstractNote = {We report that to achieve universal quantum computation using continuous variables, one needs to jump out of the set of Gaussian operations and have a nonGaussian element, such as the cubic phase gate. However, such a gate is currently very difficult to implement in practice. Here we introduce an experimentally viable “repeatuntilsuccess” approach to generating the cubic phase gate, which is achieved using sequential photon subtractions and Gaussian operations. Ultimately, we find that our scheme offers benefits in terms of the expected time until success, as well as the fact that we do not require any complex offline resource state, although we require a primitive quantum memory.},
doi = {10.1103/PhysRevA.91.032321},
journal = {Physical Review. A},
number = 3,
volume = 91,
place = {United States},
year = 2015,
month = 3
}
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