QUANTUM PROJECTION NOISE - POPULATION FLUCTUATIONS IN 2-LEVEL SYSTEMS

被引:492
作者
ITANO, WM
BERGQUIST, JC
BOLLINGER, JJ
GILLIGAN, JM
HEINZEN, DJ
MOORE, FL
RAIZEN, MG
WINELAND, DJ
机构
来源
PHYSICAL REVIEW A | 1993年 / 47卷 / 05期
关键词
D O I
10.1103/PhysRevA.47.3554
中图分类号
O43 [光学];
学科分类号
070207 ; 0803 ;
摘要
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. In one experiment, a single Hg-199+ ion, confined in a linear rf trap, was prepared in various superpositions of two hyperfine states. In another experiment, groups of Be-9+ ions, ranging in size from about 5 to about 400 ions, were confined in a Penning trap and prepared in various superposition states. The measured population fluctuations were greater when the state amplitudes were equal than when one of the amplitudes was nearly zero, in agreement with the predictions of quantum mechanics. These fluctuations, which we call quantum projection noise, are the fundamental source of noise for population measurements with a fixed number of atoms. These fluctuations are of practical importance, since they contribute to the errors of atomic frequency standards.
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页码:3554 / 3570
页数:17
相关论文
共 48 条
  • [1] COOPERATIVE BEHAVIOR OF ATOMS IRRADIATED BY BROAD-BAND SQUEEZED LIGHT
    AGARWAL, GS
    PURI, RR
    [J]. PHYSICAL REVIEW A, 1990, 41 (07): : 3782 - 3791
  • [2] ATOMIC COHERENT STATES IN QUANTUM OPTICS
    ARECCHI, FT
    THOMAS, H
    GILMORE, R
    COURTENS, E
    [J]. PHYSICAL REVIEW A, 1972, 6 (06): : 2211 - &
  • [3] STATISTICAL INTERPRETATION OF QUANTUM MECHANICS
    BALLENTI.LE
    [J]. REVIEWS OF MODERN PHYSICS, 1970, 42 (04) : 358 - &
  • [4] RESOURCE LETTER IQM-2 - FOUNDATIONS OF QUANTUM-MECHANICS SINCE THE BELL INEQUALITIES
    BALLENTINE, LE
    [J]. AMERICAN JOURNAL OF PHYSICS, 1987, 55 (09) : 785 - 792
  • [5] Bevington P., 1969, DATA REDUCTION ERROR
  • [6] TEST OF THE LINEARITY OF QUANTUM-MECHANICS BY RF SPECTROSCOPY OF THE BE-9+ GROUND-STATE
    BOLLINGER, JJ
    HEINZEN, DJ
    ITANO, WM
    GILBERT, SL
    WINELAND, DJ
    [J]. PHYSICAL REVIEW LETTERS, 1989, 63 (10) : 1031 - 1034
  • [7] A 303-MHZ FREQUENCY STANDARD BASED ON TRAPPED BE+ IONS
    BOLLINGER, JJ
    HEINZEN, DJ
    ITANO, WM
    GILBERT, SL
    WINELAND, DJ
    [J]. IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT, 1991, 40 (02) : 126 - 128
  • [8] STATIC PROPERTIES OF A NON-NEUTRAL BE-9+ -ION PLASMA
    BREWER, LR
    PRESTAGE, JD
    BOLLINGER, JJ
    ITANO, WM
    LARSON, DJ
    WINELAND, DJ
    [J]. PHYSICAL REVIEW A, 1988, 38 (02): : 859 - 873
  • [9] RADIATIVE LIFETIMES OF METASTABLE STATES OF HG+ AND HG2+
    CALAMAI, AG
    JOHNSON, CE
    [J]. PHYSICAL REVIEW A, 1990, 42 (09): : 5425 - 5432
  • [10] QUANTUM INTERFERENCE AND COLLAPSE OF THE WAVE-FUNCTION IN CAVITY QED
    CARMICHAEL, HJ
    BRECHA, RJ
    RICE, PR
    [J]. OPTICS COMMUNICATIONS, 1991, 82 (1-2) : 73 - 79