Coherent fibre link for synchronization of delocalized atomic clocks
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081731%3A_____%2F22%3A00555126" target="_blank" >RIV/68081731:_____/22:00555126 - isvavai.cz</a>
Alternative codes found
RIV/63839172:_____/22:10133381
Result on the web
<a href="https://opg.optica.org/oe/fulltext.cfm?uri=oe-30-4-5450&id=469194" target="_blank" >https://opg.optica.org/oe/fulltext.cfm?uri=oe-30-4-5450&id=469194</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1364/OE.447498" target="_blank" >10.1364/OE.447498</a>
Alternative languages
Result language
angličtina
Original language name
Coherent fibre link for synchronization of delocalized atomic clocks
Original language description
Challenging experiments for tests in fundamental physics require highly coherent optical frequency references with suppressed phase noise from hundreds of kHz down to mu Hz of Fourier frequencies. It can be achieved by remote synchronization of many frequency references interconnected by stabilized optical fibre links. Here we describe the path to realize a delocalized optical frequency reference for spectroscopy of the isomeric state of the nucleus of Thorium-229 atom. This is a prerequisite for the realization of the next generation of an optical clock the nuclear clock. We present the established 235 km long phase-coherent stabilized cross-border fibre link connecting two delocalized metrology laboratories in Brno and Vienna operating highly-coherent lasers disciplined by active Hydrogen masers through optical frequency combs. A significant part (up to tens of km) of the optical fibre is passing urban combined collectors with a non-negligible level of acoustic interference and temperature changes, which results in a power spectral density of phase noise over 10(5) rad(2).Hz(-1). Therefore, we deploy a digital signal processing technique to suppress the fibre phase noise over a wide dynamic range of phase fluctuations. To demonstrate the functionality of the link, we measured the phase noise power spectral density of a remote beat note between two independent lasers, locked to high-finesse stable resonators. Using optical frequency combs at both ends of the link, a long-term fractional frequency stability in the order of 10(-15) between local active Hydrogen masers was measured as well. Thanks to this technique, we have achieved reliable operation of the phase-coherent fibre link with fractional stability of 7 x 10(-18) in 10(3) s.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10306 - Optics (including laser optics and quantum optics)
Result continuities
Project
Result was created during the realization of more than one project. More information in the Projects tab.
Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2022
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Optics Express
ISSN
1094-4087
e-ISSN
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Volume of the periodical
30
Issue of the periodical within the volume
4
Country of publishing house
US - UNITED STATES
Number of pages
15
Pages from-to
5450-5464
UT code for WoS article
000754931700066
EID of the result in the Scopus database
2-s2.0-85124801866