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 Ciencjournal_title
Anais da Academia Brasileira de Cienciasauthors
Ahmed M,Magalhães DV,Bebeachibuli A,Müller ST,Alves RF,Ortega TA,Weiner J,Bagnato VSdoi
10.1590/s0001-37652008000200002subject
Has Abstractpub_date
2008-06-01 00:00:00pages
217-52issue
2eissn
0001-3765issn
1678-2690pii
S0001-37652008000200002journal_volume
80pub_type
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