Abstract Details

Name: Subhadeep De
Affiliation: IUCAA
Conference ID: ASI2021_614
Title : Optical Atomic Clocks to Probe Fundamental Science
Authors and Co-Authors : Subhadeep De
Abstract Type : Invited
Abstract Category : Instrumentation and Techniques
Abstract : Probing fundamental science is very important to find yet unanswered questions in nature: Astronomy-Astrophysics & Atomic-Optical Physics are two important and closely connected pathways for such investigations. Starting from Galileo's time until today, observational astronomy covers almost the entire electro-magnetic (EM) spectrum and gravitational waves (GW). Associated state-of-the-art instruments for the present observational astronomy are based on classical technologies. The future demands incorporating quantum-enhanced technologies in the present detectors, such as squeezed states of light that is planned to be used in Advance-LIGO. Further, worldwide heroic efforts are going on to develop quantum-phenomena based novel sensors for ultra-sensitive measurements, such as optical atomic clocks and atom interferometers, nano/micro fabricated opto-electro-mechanical systems, etc. There are several existing proposals to measure quantum gravity, dark matter, dark energy, CMB, GW using these quantum devices, which are yet to be realized. This lecture shall focus on optical atomic clock development at the Precision and Quantum Measurement lab (PQM-lab) at IUCAA that is planned to be used to study fundamental science. In present days' optical atomic clocks are accurate to few parts in 10-19 that corresponds to missing of just one "tick" over 34 billion years. Such clocks have been realized by accurate measurement of the highly forbidden atomic transition frequencies (clock transition) in the optical domain. There are two different systems: neutral atoms stored in an optical lattice and single atomic-ion trapped in an electrodynamic trap; for experimental measurement of the clock transitions with extreme precision. Both of these clocks use sophisticated technologies and only a few countries are able to develop them so far. Other than applications of such clocks for accurate timekeeping, which is a requisite for advanced technologies such as navigation, communication, surveillance, meteorology, and so on, the scientific community is always enthusiastic to develop optical atomic clocks since they are useful to reveal unanswered questions in science. The present advanced communication technologies together with the long-distance transfer of the optical photons allow intercomparison of the geographically distributed state-of-the-art optical clocks. Optical atomic clocks and networking among them uplift the capability to probe fundamental aspects of science such as the constancy of the dimensionless fundamental constants, violation of the fundamental symmetries, geodetic measurements, and so on.