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Quantum Projection Noise: Population Fluctuations in 2-Level Systems

Published

Author(s)

Wayne M. Itano, James C. Bergquist, John J. Bollinger, J M. Gilligan, D J. Heinzen, F L. Moore, M G. Raizen, David J. Wineland

Abstract

Measurements of internal energy states of atomic ions confined in traps can be used to illustrate fundamental properties of quantum systems, because long relaxation times and observation times are available. In the experiments described here, a single ion or a few identical ions were prepared in well-defined superpositions of two internal energy eigenstates. The populations of the energy levels were then measured. For an individual ion, the outcome of the measurement is uncertain, unless the amplitude for one of the two eigenstates is zero, and is completely uncertain when the magnitudes of the two amplitudes are equal.
Citation
Physical Review A (Atomic, Molecular and Optical Physics)
Volume
47

Citation

Itano, W. , Bergquist, J. , Bollinger, J. , Gilligan, J. , Heinzen, D. , Moore, F. , Raizen, M. and Wineland, D. (1993), Quantum Projection Noise: Population Fluctuations in 2-Level Systems, Physical Review A (Atomic, Molecular and Optical Physics), [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=104953 (Accessed October 28, 2021)
Created January 1, 1993, Updated February 17, 2017