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Keeping a Quantum Bit Alive by Optimized $π$-Pulse Sequences

Götz S. Uhrig
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Abstract

A general strategy to maintain the coherence of a quantum bit is proposed. The analytical result is derived rigorously including all memory and back-action effects. It is based on an optimized $π$-pulse sequence for dynamic decoupling extending the Carr-Purcell-Meiboom-Gill (CPMG) cycle. The optimized sequence is very efficient, in particular for strong couplings to the environment.

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Götz S. Uhrig. 2007-02-08. Keeping a Quantum Bit Alive by Optimized $π$-Pulse Sequences. https://doi.org/10.1103/physrevlett.98.100504

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