30/5/2008, 11 am, room A2-07

Speaker: Eduardo Peres Novais de Sá

Title: Resilient Quantum Computation in Correlated Environments: A Quantum Phase Transition Perspective

Abstract: In the theory of quantum error correction (QEC) the “threshold theorem” states: Provided the noise strength is below a critical value, quantum information can be protected for arbitrarily long times. This remarkable theorem was first derived for environments in which the spatial and temporal correlations decay exponentially. Although there is still some controversy, the theorem is widely accepted by a community where the foremost effort has been to extend it to correlated error models. In this presentation, I will first present a brief description of QEC from a physicist’s perspective. Furthermore, it will be discussed how to extend the “threshold theorem” to environments with power law correlations. Finally, a parallel with the theory of quantum phase transitions will be made.