Advances in Natural Sciences Nanoscience and Nanotechnology

Quantum dynamics of quantum bits

Bich Ha Nguyen

Published Jul 7, 2011• 4 citations

Abstract

Abstract The theory of coherent oscillations of the matrix elements of the density matrix of the two-state system as a quantum bit is presented. Different calculation methods are elaborated in the case of a free quantum bit. Then the most appropriate methods are applied to the study of the density matrices of the quantum bits interacting with a classical pumping radiation field as well as with the quantum electromagnetic field in a single-mode microcavity. The theory of decoherence of a quantum bit in Markovian approximation is presented. The decoherence of a quantum bit interacting with monoenergetic photons in a microcavity is also discussed. The content of the present work can be considered as an introduction to the study of the quantum dynamics of quantum bits.

DOI: 10.1088/2043-6262/2/3/033002

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