Physica Scripta

Quantum theory of the coherently pumped micromaser

István Németh, János A. Bergou

Published Jul 1, 2009• 0 citations

Abstract

Detailed theoretical and experimental study of the atom–field interaction starting from first principles was made possible by the realization of the single-atom micromaser. The situation realized in a micromaser is very close to the ideal case of a single two-level atom interacting with a single quantized mode of a superconducting cavity. This system's ability to coherently transfer quantum states between atoms and photons made it relevant in the context of quantum computation as well. Although considerable work, both theoretical and experimental, has been devoted to this system, with a few exceptions, most cases involved only non-coherent pumping. As a result, the density matrix describing the cavity field remained diagonal, preventing the appearance of coherences. Here, our goal is to provide a summary of the progress we made toward a comprehensive understanding of the features of the coherently pumped micromaser with special respect to coherences, which are central to quantum information processing.

DOI: 10.1088/0031-8949/2009/t135/014017

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