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Title: Graph-state basis for Pauli channels

Abstract

Quantum capacities of Pauli channels are not additive, a degenerate quantum code may improve the hashing bound of the capacity. The difficulty in approaching the capacity is how to calculate the coherent information of a generic degenerate quantum code. Using graph state basis, we greatly reduce the problem for the input of quantum error-correcting code. We show that for a graph diagonal state passing through a Pauli channel the output state is diagonalizable and the joint output state of the system and ancilla is block diagonalizable. When the input state is an equal probable mixture of codewords of a stabilizer code, the coherent information can be analytically obtained.

Authors:
;  [1]
  1. College of Information and Electronic Engineering, Zhejiang Gongshang University, Hangzhou, 310018 (China)
Publication Date:
OSTI Identifier:
21546733
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 83; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevA.83.052316; (c) 2011 American Institute of Physics
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COMPUTER CODES; ERRORS; GRAPH THEORY; PAULI PRINCIPLE; QUANTUM INFORMATION; QUANTUM OPERATORS; INFORMATION; MATHEMATICAL OPERATORS; MATHEMATICS

Citation Formats

Chen Xiaoyu, and Jiang Lizhen. Graph-state basis for Pauli channels. United States: N. p., 2011. Web. doi:10.1103/PHYSREVA.83.052316.
Chen Xiaoyu, & Jiang Lizhen. Graph-state basis for Pauli channels. United States. doi:10.1103/PHYSREVA.83.052316.
Chen Xiaoyu, and Jiang Lizhen. 2011. "Graph-state basis for Pauli channels". United States. doi:10.1103/PHYSREVA.83.052316.
@article{osti_21546733,
title = {Graph-state basis for Pauli channels},
author = {Chen Xiaoyu and Jiang Lizhen},
abstractNote = {Quantum capacities of Pauli channels are not additive, a degenerate quantum code may improve the hashing bound of the capacity. The difficulty in approaching the capacity is how to calculate the coherent information of a generic degenerate quantum code. Using graph state basis, we greatly reduce the problem for the input of quantum error-correcting code. We show that for a graph diagonal state passing through a Pauli channel the output state is diagonalizable and the joint output state of the system and ancilla is block diagonalizable. When the input state is an equal probable mixture of codewords of a stabilizer code, the coherent information can be analytically obtained.},
doi = {10.1103/PHYSREVA.83.052316},
journal = {Physical Review. A},
number = 5,
volume = 83,
place = {United States},
year = 2011,
month = 5
}
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