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Information × Registration Number 0212U009080, 0112U004442 , R & D reports Title Nuclear clock based on 229 Thorium. popup.stage_title Head Yatsenko Leonid Petrovych, Registration Date 28-12-2012 Organization Institute of physics NASU popup.description2 Object of investigation: the atoms and ions of 229Th in the coherent light field. Purpose of investigation: - the development of a theoretical model of "ionic" nuclear frequency standard with the nucleus excited by polychromatic laser field (a femtosecond frequency comb), modeling and investigation of the dependence of frequency stability of the single-ion nuclear standard on the parameters of optical radiation when nuclei are excited by the polychromatic laser field. Method of investigation: analysis of processes of the resonant interaction of laser radiation with matter using the density matrix approach and Monte Carlo method for the wave function. The description of the motion of atoms in a trap with Newton's equations. Theoretical results: the computations of main parameters of two-photon excitation of the ion Th3+ by the field of light pulses has been carried out. It is shown that under realistic parameters one can achieve the saturated absorption of ions. To reduce the effect of fields acting on the atoms and ions, the usage of optical traps formed by sequences of counterpropagating light pulses is proposed. It is shown that an atom or an ion can be localized in a small region of space, with a linear dimension of the order of the wavelength, when the pulse parameters are properly chosen. The short laser pulses, in the numerical model of picosecond pulses, slightly perturb an ion. Various ion interrogation schemes, namely, Rabi, Ramsey, and hyper-Ramsey, has been analyzed. The fluorescence signal registration scheme, which is based on the carrier frequency sequential offset of spectroscopic laser up or down from the transition frequency, has been proposed and investigated. Novelty: the two-photon absorption of optical radiation by the thorium nuclei, proposed and investigated in the project, make it possible an efficient use of the laser pulse energy (all spectral components are effectively interact with the nuclei). Sphere of application: optical frequency standards. Product Description popup.authors Романенко Віктор Іванович Романенко Олександр Вікторович Удовицька Олена Григорівна Яценко Леонід Петрович popup.nrat_date 2020-04-02 Close