Naslov
Frequency comb polarization spectroscopy of multilevel rubidium atoms

Autori
Vujičić, Nataša

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
EGAS 44th Conference of the European Group on Atomic Systems / Hanstrop D., Hartman H., Engström L., Nilsson H., Salomonson S. - Gothenburg : European Physical Society (EPS), 2012, 61-61

ISBN
2-914771-75-4

Skup
44th Conference of the European Group on Atomic Systems

Mjesto i datum
Göteborg, Švedska, 09.07.2012. - 13.07.2012

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
frequency comb; polarization spectroscopy; rubidium; femtosecond laser; pulse train

Sažetak
The subject of this study is polarization effects induced by resonant interaction of rubidium atoms with optical frequency comb. Ultrashort, mode-locked, phase-stabilized femtosecond (fs) laser with high repetition rates produces stabilized wide-bandwidth optical frequency comb (a spectrum consisting of a series of evenly spaced sharp lines). In the previous papers, modified direct frequency comb spectroscopy (modified DFCS), which utilizes a fixed frequency comb spectrum and an additional cw scanning probe laser, was presented. It was shown that resonant excitation of room-temperature rubidium and cesium atoms by discrete frequency comb optical spectrum results in the comblike velocity distribution of the excited-state hyperfine level populations and velocity selective population transfer between the atomic ground-state hyperfine levels. Detailed theoretical investigation of the fs pulse train interaction with multilevel atom was performed, provided not only qualitative but also quantitative description of the interacting atom-laser system, as was illustrated by the excellent agreement with the experimental results. The effect of velocity selective optical pumping (VSOP), induced by frequency comb excitation, gave us novel information about the frequency comb excitation in Doppler-broadened atomic systems. Here, we present the experimental study of Zeeman components optical pumping effects, induced by interaction with circularly polarized fs laser pump laser in external static magnetic field resulting in induced anisotropy of medium. If such, optically prepared, medium is examined by linearly polarized continuous-wave (cw) probe laser, the effects of rotation of polarization of probe beam can be observed. Such polarizations effects, induced by interaction of atoms with optical frequency comb are, as far as we know, for the first time experimentally studied. The phenomenon of polarization rotation of a weak linearly polarized cw optical field in room-temperature rubidium vapor have been investigated for different polarizations of the fs pump laser (left and right circular polarization), in dependence on fs pump laser power as well as on external magnetic field strength. Semi-classical model of probe beam propagation through anisotropic medium gives good description of system and is in accordance with observed experimental results.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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