Advances in the accuracy, stability, and reliability of the PTB primary fountain clocks

被引：119

作者：

Weyers, S. ^{[1
]}

Gerginov, V ^{[1
,3
,4
]}

Kazda, M. ^{[1
]}

Rahm, J. ^{[1
]}

Lipphardt, B. ^{[1
]}

Dobrev, G. ^{[1
,5
]}

Gibble, K. ^{[2
]}

机构：

[1] PTB, Bundesallee 100, D-38116 Braunschweig, Germany

[2] Penn State Univ, Dept Phys, University Pk, PA 16802 USA

[3] NIST, Boulder, CO 80305 USA

[4] Univ Colorado, Dept Phys, Boulder, CO 80309 USA

[5] Sofia Univ St Kliment Ohridski, Fac Phys, 5 J Bourchier Blvd, Sofia 1164, Bulgaria

来源：

METROLOGIA | 2018年 / 55卷 / 06期

基金：

美国国家科学基金会;

关键词：

atomic fountain clocks; primary frequency standards; SI second; international atomic time; frequency metrology; DISTRIBUTED CAVITY PHASE; PRIMARY FREQUENCY STANDARDS; ATOMIC CESIUM FOUNTAIN; UNCERTAINTY EVALUATION; SHIFTS; REALIZATION; TRANSITIONS; SUPPRESSION; OSCILLATOR; SPECTRUM;

D O I：

10.1088/1681-7575/aae008

中图分类号：

TH7 [仪器、仪表];

学科分类号：

0804 ; 080401 ; 081102 ;

摘要：

Improvements of the systematic uncertainty, frequency instability, and long-term reliability of the two caesium fountain primary frequency standards CSF1 and CSF2 at PTB (Physikalisch-Technische Bundesanstalt) are described. We have further investigated many of the systematic effects and made a number of modifications of the fountains. With an optically stabilized microwave oscillator, the quantum projection noise limited frequency instabilities are improved to 7.2 x 10(-14) (tau/1 s)(-1/2) for CSF1 and 2.5 x 10(-14) (tau/1 s)(-1/2) for CSF2 at high atom density. The systematic uncertainties of CSF1 and CSF2 are reduced to 2.74 x 10(-16) and 1.71 x 10(-16), respectively. Both fountain clocks regularly calibrate the scale unit of International Atomic Time (TAI) and the local realization of Coordinated Universal Time, UTC(PTB), and serve as references to measure the frequencies of local and remote optical frequency standards.

引用

页码：789 / 805

页数：17

共 85 条

[1] Systematic Uncertainty Evaluation of the Cesium Fountain Primary Frequency Standard at NPL India [J].