Automated error correction in superdense coding, with implementation on superconducting quantum computer

TL;DR

This paper introduces a task-specific, automated error correction method for superdense coding algorithms, implemented on superconducting quantum computers, enhancing fidelity and robustness against noise with minimal complexity increase.

Contribution

It presents a novel automated error correction technique for superdense coding using non-destructive Bell state discrimination, implemented without measurements during operation, and experimentally validated on IBM quantum hardware.

Findings

High fidelity demonstrated in experimental results

Effective error correction on 7-qubit superconducting quantum computer

Successful implementation on 27-qubit quantum simulator

Abstract

Construction of a fault-tolerant quantum computer remains a challenging problem due to unavoidable noise in quantum states and the fragility of quantum entanglement. However, most of the error-correcting codes increases the complexity of the algorithms, thereby decreasing any quantum advantage. Here we present a task-specific error-correction technique that provides a complete protection over a restricted set of quantum states. Specifically, we give an automated error correction in Superdense Coding algorithms utilizing n-qubit generalized Bell states. At its core, it is based on non-destructive discrimination method of Bell states involving measurements on ancilla qubits (phase and parity ancilla). The algorithm is shown to be distributable and can be distributed to any set of parties sharing orthogonal states. Automated refers to experimentally implementing the algorithm in a quantum computer by utilizing unitary operators with no measurements in between and thus without the need for outside intervention. We also experimentally realize our automated error correction technique for three different types of superdense coding algorithm on a 7-qubit superconducting IBM quantum computer and also on a 27-qubit quantum simulator in the presence of noise. Probability histograms are generated to show the high fidelity of our experimental results. Quantum state tomography is also carried out with the quantum computer to explicate the efficacy of our method.