The Brazilian time and frequency atomic standards program.

Abstract:

:Cesium atomic beam clocks have been the workhorse for many demanding applications in science and technology for the past four decades. Tests of the fundamental laws of physics and the search for minute changes in fundamental constants, the synchronization of telecommunication networks, and realization of the satellite-based global positioning system would not be possible without atomic clocks. The adoption of optical cooling and trapping techniques, has produced a major advance in atomic clock precision. Cold-atom fountain and compact cold-atom clocks have also been developed. Measurement precision of a few parts in 10(15) has been demonstrated for a cold-atom fountain clock. We present here an overview of the time and frequency metrology program based on cesium atoms under development at USP São Carlos. This activity consists of construction and characterization of atomic-beam, and several variations of cold-atom clocks. We discuss the basic working principles, construction, evaluation, and important applications of atomic clocks in the Brazilian program.

journal_name

An Acad Bras Cienc

authors

Ahmed M,Magalhães DV,Bebeachibuli A,Müller ST,Alves RF,Ortega TA,Weiner J,Bagnato VS

doi

10.1590/s0001-37652008000200002

subject

Has Abstract

pub_date

2008-06-01 00:00:00

pages

217-52

issue

2

eissn

0001-3765

issn

1678-2690

pii

S0001-37652008000200002

journal_volume

80

pub_type

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