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Information × Registration Number 0211U005707, 0111U004953 , R & D reports Title Nuclear clock based on 229 Thorium. popup.stage_title Head Yatsenko Leonid Petrovych, Registration Date 22-12-2011 Organization Institute of physics NASU popup.description2 Object of investigation: 229Th nucleus in a coherent light field. Purpose of investigation: - the development of a theoretical model for the error signal in "solid" nuclear frequency standard if the nucleus is excited with polychromatic laser field (a femtosecond frequency comb), the development of an algorithm to compute and model the formation of this signal. Method of investigation: analysis of process of the resonant interaction of laser radiation with matter using Schr?dinger equation and the density matrix equation. An important issue in investigation of a frequency standard is the values of light shifts, which determine the ultimate accuracy of the standard. In our studies the stability of the nuclear frequency standard can be of the order of 10-19-10-18, both for single-photon and two-photon excitation schemes. The possibility of realizing two-photon transition is caused by non-zero magnetic dipole moments in the ground and excited states. Usage of femtosecond frequency comb can be the basic method for the accurate measurement of the transition frequency in the nucleus. Compared with single-photon, two-photon scheme has the following advantages: 1) all the spectral components (pairwise) form the fluorescence signal; 2) in the field of counterpropagating pulses the linear Doppler shift of the resonance is absent; 3) to develop a frequency standard one needs a source of radiation with two times smaller wavelength (approximately 320 nm); 4) the problem of background signal is absent; 5) in Th3+ ions one can expect much more effective two-photon excitation than one photon excitation at moderate intensities (of the order of 1 W/cm2 and less). We propose the interrogation scheme for solid-state standardy together with its numerical simulation. The precision of its accuracy tuning at resonance is about 1 Hz. Product Description popup.authors Романенко Віктор Іванович Романенко Олександр Вікторович Удовицька Олена Григорівна Яценко Леонід Петрович popup.nrat_date 2020-04-02 Close