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Journal of Modern Optics

Longitudinal quantum beam tomography

David A. Kokorowski, David E. Pritchard

Published Nov 1, 1997• 12 citations
Publisher

Abstract

We propose an experiment to determine the density operator for the longitudinal quantum state of an atomic beam. The method is based on tomographic reconstruction of the Wigner function via a set of measured probability distributions for the phase-space rotated position operator. The time evolution of the Wigner function in free space effectively performs the required phase-space rotation. We propose a state-selective time-dependent technique for measuring longitudinal probability distributions.

DOI
10.1080/09500349708231902

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We propose an experiment to determine the density operator for the longitudinal quantum state of an atomic beam. The method is based on tomographic reconstruction of the Wigner function via a set of measured probability distributions for the phase-space rotated position operator. The time evolution of the Wigner function in free space effectively performs the required phase-space rotation. We propose a state-selective time-dependent technique for measuring longitudinal probability distributions.
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In the past few years experimenters have learned how to determine the complete quantum state of an ensemble of particles or fields which have been prepared according to some unknown procedure. Through these experiments they have answered a question posed by W. Pauli in the 1930s. The methods used involve measuring statistical distributions of a well chosen set of physical observables and using a tomographic inversion algorithm to reconstruct the Wigner function and its corresponding wave function or density matrix. Recontructions have been successfully carried out in atomic, molecular, and optical physics. The development of these procedures helps to firm up the interpretation of the Schrodinger wave function.
In the past few years experimenters have learned how to determine the complete quantum state of an ensemble of particles or fields which have been prepared according to some unknown procedure. Through these experiments they have answered a question posed by W. Pauli in the 1930s. The methods used involve measuring statistical distributions of a well chosen set of physical observables and using a tomographic inversion algorithm to reconstruct the Wigner function and its corresponding wave function or density matrix. Recontructions have been successfully carried out in atomic, molecular, and optical physics. The development of these procedures helps to firm up the interpretation of the Schrodinger wave function.