Journal of Zhejiang University(Engineering Science)
Study on a quantum cyclic code for correcting two or more quantum errors
Xiao Chen
Abstract
The condition for constructing quantum cyclic codes of prime code length p with form8j+ 3was obtained via the quadratic residue method.A theorem on the form of quantum cyclic codes'generating ma- trix was proved.As an example,directexamination of digital computation showed thatthe quantum cyclic code for encoding 1 9qubits into 1 qubit and correcting 3errors satisfies error- correcting conditions.This code has never been reported in literature as far as we know.Another method for determining the already known quantum cyclic code for encoding1 1 qubits into1 qubit and correcting2 errors is given.Extended generating matrix method is proposed to express the error- correcting condition,which requires that the boolean summation of every four columns of the extended generating matrix should notbe an all zeros col- umn for codes correcting two errors.Meanwhile a quantum code should be self- orthogonal,that is the symplectic inner products of each pair of generating vectors should be zero.The codes we obtained satisfy all these conditions.