An Isaac Newton Institute Workshop

Entanglement and Transfer of Quantum Information

Quantum closed-loop control and error correction.

Authors: Milburn (University of Queensland), Sarovar (University of Queensland)

Abstract

In this talk I will explore connections between quantum error correction and closed-loop quantum feedback. A simple model, based on detected measurement errors, in which the measurements are continuous in time will be presented. Error correction is implemented using the Poisson process feed-back model. I will also discuss a new scheme based on continuous measurement and feed-back that can increase the coherence time for a single encoded qubit. Finally I will discuss schemes that explicitly use decoherence for ancilla qubits, without reference to an explicit measured signal. These show how quantum closed-loop control may be used to increase the coherence time of encoded qubits.