Quantum correction with three codes (original) (raw)

Digital System Design for Quantum Error Correction Codes

Quantum computing is a computer development technology that uses quantum mechanics to perform the operations of data and information. It is an advanced technology, yet the quantum channel is used to transmit the quantum information which is sensitive to the environment interaction. Quantum error correction is a hybrid between quantum mechanics and the classical theory of error-correcting codes that are concerned with the fundamental problem of communication, and/or information storage, in the presence of noise. e interruption made by the interaction makes transmission error during the quantum channel qubit. Hence, a quantum error correction code is needed to protect the qubit from errors that can be caused by decoherence and other quantum noise. In this paper, the digital system design of the quantum error correction code is discussed. ree designs used qubit codes, and nine-qubit codes were explained. e systems were designed and configured for encoding and decoding ninequbit error correction codes. For comparison, a modified circuit is also designed by adding Hadamard gates.

Introduction to quantum error correction

Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 1998

Quantum states are very delicate, so it is likely some sort of quantum error correction will be necessary to build reliable quantum computers. The theory of quantum error-correcting codes has some close ties to and some striking differences from the theory of classical error-correcting codes. Many quantum codes can be described in terms of the stabilizer of the codewords. The stabilizer is a finite Abelian group, and allows a straightforward characterization of the error-correcting properties of the code. The stabilizer formalism for quantum codes also illustrates the relationships to classical coding theory, particularly classical codes over GF(4), the finite field with four elements.

Simulating the Effects of Quantum Error-correction Schemes

It is important to protect quantum information against decoherence and operational errors, and quantum error-correcting (QEC) codes are the keys to solving this problem. Of course, just the existence of codes is not efficient. It is necessary to perform operations fault-tolerantly on encoded states because error-correction process (i.e., encoding, decoding, syndrome measurement and recovery) itself induces an error. By using simulation, this paper investigates the effects of some important QEC codes (the five qubit code, the seven qubit code and the nine qubit code) and their fault-tolerant operations when the error-correction process itself induces an error. The corresponding results, statistics and analyses are presented in this paper.

4 Quantum

2016

In this paper, we provide an implementation of five, seven and ninequbits error correcting codes on a classical computer using the quantum simulator Feynman program. We also compare the three codes by computing the fidelity when double errors occurs in a depolarizing channel. As triple errors and more are considered very unlikely, it has negligible effect on the next results.

Quantum Error Correction Methods

2016

This study surveys the mathematical structure of a quantum error correcting codes and the way they are developed through certain stages of error correction. In particular, the families of Calderbank-Shor-Steane codes (CSS) and the stabilizer codes are discussed and through elaborative examples it will be shown that the CSS codes are in the family of the stabilizer codes. Since the study of the CSS codes depends on a firm knowledge of classical coding theory, a rigorous mathematical review of the linear codes is done separately. Analysing the structure of the stabilizer formalism is highly depended on the effective use of some group theoretic notions. This structure is discussed in more detail and examples will be given. As the ultimate application of the quantum error correction the rules of the fault-tolerant quantum computing is explored and finding the threshold condition of an example will be done.

Approximate quantum error correction can lead to better codes

Physical Review A, 1997

We present relaxed criteria for quantum error correction which are useful when the specific dominant quantum noise process is known. These criteria have no classical analogue. As an example, we provide a four-bit code which corrects for a single amplitude damping error. This code violates the usual Hamming bound calculated for a Pauli description of the error process, and does not fit into the GF(4) classification.

Entanglement increases the error-correcting ability of quantum error-correcting codes

Physical Review A, 2013

If entanglement is available, the error-correcting ability of quantum codes can be increased. We show how to optimize the minimum distance of an entanglement-assisted quantum error-correcting (EAQEC) code, obtained by adding ebits to a standard quantum error-correcting code, over different encoding operators. By this encoding optimization procedure, we found several new EAQEC codes, including a family of [[n, 1, n; n − 1]] EAQEC codes for n odd and code parameters [[7, 1, 5; 2]], [[7, 1, 5; 3]], [[9, 1, 7; 4]], [[9, 1, 7; 5]], which saturate the quantum singleton bound for EAQEC codes.

Error Correction in Quantum Communication

1996

We show how procedures which can correct phase and amplitude errors can be directly applied to correct errors due to quantum entanglement. We specify general criteria for quantum error correction, introduce quantum versions of the Hamming and the Gilbert-Varshamov bounds and comment on the practical implementation of quantum codes.

Approximate quantum error-correcting codes

It is a standard result in the theory of quantum error-correcting codes that no code of length n can fix more than n/4 arbitrary errors, regardless of the dimension of the coding and encoded Hilbert spaces. However, this bound only applies to codes which exactly correct errors. Naively, one might expect that correcting errors to very high fidelity would only allow small violations of this bound. However, this intuition is incorrect: we construct in this paper quantum error-correcting codes capable of correcting up to n/2 − 1 arbitrary errors with fidelity exponentially close to 1. This demonstrates a severe distinction between exact quantum error correction and approximate quantum error correction.

Quantum Error Correction for Communication

Physical Review Letters, 1996

We show how procedures which can correct phase and amplitude errors can be directly applied to correct errors due to quantum entanglement. We specify general criteria for quantum error correction, introduce quantum versions of the Hamming and the Gilbert-Varshamov bounds and comment on the practical implementations of quantum codes.