2005/11/21 by Shimshon Kallush, S. Kallush, Ronnie Kosloff +1
Computer Science · Physics and Astronomy · #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #quant-ph
paper · pdf · doi:10.1103/physreva.73.032324
arxiv created 2005/11/21 · openalex publication_date 2006/03/17 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The problem of automatically protecting a quantum system against noise in a closed circuit is analyzed. A general scheme is developed built from two steps. First, a distillation step is induced in which undesired components are removed to another degree of freedom of the system. Later a recovering step is employed in which the system gains back its initial density. An optimal-control method is used to generate the distilling operator. The scheme is demonstrated by a simulation of a two-level bit influenced by white noise. Undesired deviations from the target were shown to be reduced by at least two orders of magnitude on average. The relations between the quantum version of the classical Watt's governor and the field of quantum information are also discussed.