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PHOTONICS AND OPTOINFORMATICS
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535:621.373.826]:539
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TWO-DIMENSIONAL LOCALIZATION OF ATOMIC POPULATIONS
IN FOUR-LEVEL QUANTUM SYSTEMS
E.A. Efremova
a, M.Yu. Gordeev
a, Yu.V. Rozhdestvensky
a aITMO University, Saint Petersburg, Russia, mxmgordeev@gmail.com
Abstract. The paper deals with investigation of one aspect of fundamental problem of laser radiation interaction with the matter. This problem is spatial localization of atomic populations due to fields impact of few running waves. We are the first to propose in our work two–dimensional spatial localization of atomic populations in medium with tripod–like configuration of levels under the field influence of running waves only. Three running waves, propagating along one plane 120o angle-wise to each other, form the system of standing waves in this plane. Atomic populations can be localized in the field of these standing waves. Moreover, the degree of such localization can make up hundredth parts of the wavelength of the incident optical radiation. It is shown that an excitation of the central transition of the tripod-like system using a field of multidirectional linearly polarized running waves is the necessary condition of the population dependence from spatial coordinates in the XY – plane. The two–dimensional shapes that appear in this system can have very complicated structure such as “double – craters”.
Keywords: spatial localization, tripod – scheme, atomic populations.
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А а в а
–
, Efremova.kate@gmail.com- , , , - ,вМа Ю ь в ч
–
, И , - , ,mxmgordeev@gmail.com
Р в Ю
а в ч
–
И , -- , , rozd-yu@mail.ru, ,Ekaterina A. Efremova
–
PhD, Associate professor, Saint Petersburg State University, Saint Petersburg, Russia,Efremova.kate@gmail.com
Maxim Yu. Gordeev
–
postgraduate, Saint Petersburg State University, Saint Petersburg, Russia,mxmgordeev@gmail.com
Yuri V. Rozhdestvensky
–
D.Sc., Senior scientific researcher, ITMO University, Saint Petersburg, Russia,rozd-yu@mail.ru
