Error Correcting Codes for Binary Unitary Channels on Multipartite Quantum Systems

Good quantum error-correcting codes exist.

A quantum error-correcting code is defined to be a unitary mapping ~encoding! of k qubits ~two-state quantum systems! into a subspace of the quantum state space of n qubits such that if any t of the qubits undergo arbitrary decoherence, not necessarily independently, the resulting n qubits can be used to faithfully reconstruct the original quantum state of the k encoded qubits. Quantum error-co...

One-point Goppa Codes on Some Genus 3 Curves with Applications in Quantum Error-Correcting Codes

We investigate one-point algebraic geometric codes CL(D, G) associated to maximal curves recently characterized by Tafazolian and Torres given by the affine equation yl = f(x), where f(x) is a separable polynomial of degree r relatively prime to l. We mainly focus on the curve y4 = x3 +x and Picard curves given by the equations y3 = x4-x and y3 = x4 -1. As a result, we obtain exact value of min...

Multipartite entanglement, quantum- error-correcting codes, and entangling power of quantum evolutions

Good Quantum Error-correcting Codes Exist. Typeset Using Revt E X 1

A quantum error-correcting code is defined to be a unitary mapping (encoding) of k qubits (2-state quantum systems) into a subspace of the quantum state space of n qubits such that if any t of the qubits undergo arbitrary decoherence, not necessarily independently, the resulting n qubits can be used to faithfully reconstruct the original quantum state of the k encoded qubits. Quantum error-corr...

The Quantum Entanglement of Binary and Bipolar Sequences

Classification of different forms of quantum entanglement is an active area of research, central to development of effective quantum computers, and similar to classification of error-correction codes, where code duality is broadened to equivalence under all ’local’ unitary transforms. We explore links between entanglement, coding theory, and sequence design, by examining multi-spectra of quantu...