The radiation force on a moving atom in a bichromatical travelling field is investigated in this paper. The relation of the atomic stimulated transition rate and the radiation force on the atom with its velocity in a bichromatical travelling wave is obtained by numberical calculation. Compared with that in a monochromatical travelling or a standing wave, the result in the bichromatical field have its own character, which is useful in the investigation of laser cooling of neutral atoms, selection of atomic velocity and atomic mometum diffusion.The radiation force on a moving atom in a bichromatical travelling field is investigated in this paper. The relation of the atomic stimulated transition rate and the radiation force on the atom with its velocity in a bichromatical travelling wave is obtained by numberical calculation. Compared with that in a monochromatical travelling or a standing wave, the result in the bichromatical field have its own character, which is useful in the investigation of laser cooling of neutral atoms, selection of atomic velocity and atomic mometum diffusion.

Acta Optica SinicaJan 1, 19930 citations

Sub-Doppler laser cooling on combined optical transitions

Прудников Олег Николаевич, E. Arimondo

We study the laser cooling process in a complex lambda system in the presence of force-assisted bichromatic velocity-selective coherent population trapping. Our theoretical model includes atomic transitions based on two ground states, Fg=1 and Fg′=3, and one excited state, Fe=2, excited by a bichromatic laser field tuned in resonance with the Fg=1→Fe=2 and Fg′=3→Fe=2 transitions. The analyzed optical scheme may be useful for alternative transverse cooling in experiments with group III atoms (Al, Ga, In).We study the laser cooling process in a complex lambda system in the presence of force-assisted bichromatic velocity-selective coherent population trapping. Our theoretical model includes atomic transitions based on two ground states, Fg=1 and Fg′=3, and one excited state, Fe=2, excited by a bichromatic laser field tuned in resonance with the Fg=1→Fe=2 and Fg′=3→Fe=2 transitions. The analyzed optical scheme may be useful for alternative transverse cooling in experiments with group III atoms (Al, Ga, In).

Journal of the Optical Society of America BMay 1, 200315 citations

Atomic phenomena in bichromatic laser fields

F. Ehlotzky

Physics ReportsMay 1, 2001172 citations

Dark-line atomic resonances in a submicron-thin Rb vapor layer

Armen D. Sargsyan, David G. Sarkisyan, A. Papoyan

We report an experimental investigation of the effect of electromagnetically induced transparency (EIT) using bichromatic laser radiation and an extremely thin cell filled with pure Rb with smoothly controllable thickness $L$ of the atomic vapor layer in the range $\ensuremath{\sim}780--1600\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$, for which $L$ is comparable to the laser wavelength $\ensuremath{\lambda}$ resonant with the ${D}_{2}$ line $(780\phantom{\rule{0.3em}{0ex}}\mathrm{nm})$ . It is revealed that the transmission spectrum of the probe laser contains two sub-Doppler peaks that have different linewidths. The narrow peak corresponds to EIT, whereas the broader one results from velocity-selective optical pumping (VSOP) and repumping processes. It is demonstrated that in the case of nonzero detuning of the coupling laser, the EIT resonance and VSOP are shifted with respect to each other on the frequency scale, which makes it possible to observe a competition between the two effects (this is not possible to realize in an ordinary cell). Also, the Dicke-type coherent narrowing effect depending on the ratio $L∕\ensuremath{\lambda}$ influences the absorption spectrum of the probe laser. Formation of an EIT resonance is substantially favored for the atoms with slow normal velocity, caused by their longer interaction time with the bichromatic laser field. As a result of the predominant contribution of these atoms, the observed linewidth of the EIT resonance is only $\ensuremath{\sim}9\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}$, which is more than ten times narrower than the inverse window-to-window flight time. In an external magnetic field, three and five EIT resonances have been observed for the vapor thickness of $L=2\ensuremath{\lambda}$, on $^{87}\mathrm{Rb}$ and $^{85}\mathrm{Rb}$ , respectively.We report an experimental investigation of the effect of electromagnetically induced transparency (EIT) using bichromatic laser radiation and an extremely thin cell filled with pure Rb with smoothly controllable thickness $L$ of the atomic vapor layer in the range $\ensuremath{\sim}780--1600\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$, for which $L$ is comparable to the laser wavelength $\ensuremath{\lambda}$ resonant with the ${D}_{2}$ line $(780\phantom{\rule{0.3em}{0ex}}\mathrm{nm})$. It is revealed that the transmission spectrum of the probe laser contains two sub-Doppler peaks that have different linewidths. The narrow peak corresponds to EIT, whereas the broader one results from velocity-selective optical pumping (VSOP) and repumping processes. It is demonstrated that in the case of nonzero detuning of the coupling laser, the EIT resonance and VSOP are shifted with respect to each other on the frequency scale, which makes it possible to observe a competition between the two effects (this is not possible to realize in an ordinary cell). Also, the Dicke-type coherent narrowing effect depending on the ratio $L∕\ensuremath{\lambda}$ influences the absorption spectrum of the probe laser. Formation of an EIT resonance is substantially favored for the atoms with slow normal velocity, caused by their longer interaction time with the bichromatic laser field. As a result of the predominant contribution of these atoms, the observed linewidth of the EIT resonance is only $\ensuremath{\sim}9\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}$, which is more than ten times narrower than the inverse window-to-window flight time. In an external magnetic field, three and five EIT resonances have been observed for the vapor thickness of $L=2\ensuremath{\lambda}$, on $^{87}\mathrm{Rb}$ and $^{85}\mathrm{Rb}$, respectively.

Physical Review AMar 2, 200661 citations

MOTION OF THE ATOM IN A LASER FIELD

WORLD SCIENTIFIC eBooksJul 1, 19982 citations

L

of the atomic vapor layer in the range $\ensuremath{\sim}780--1600\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$, for which

L

is comparable to the laser wavelength $\ensuremath{\lambda}$ resonant with the

{D}_{2}

line

(780\phantom{\rule{0.3em}{0ex}}\mathrm{nm})

. It is revealed that the transmission spectrum of the probe laser contains two sub-Doppler peaks that have different linewidths. The narrow peak corresponds to EIT, whereas the broader one results from velocity-selective optical pumping (VSOP) and repumping processes. It is demonstrated that in the case of nonzero detuning of the coupling laser, the EIT resonance and VSOP are shifted with respect to each other on the frequency scale, which makes it possible to observe a competition between the two effects (this is not possible to realize in an ordinary cell). Also, the Dicke-type coherent narrowing effect depending on the ratio $L∕\ensuremath{\lambda}$ influences the absorption spectrum of the probe laser. Formation of an EIT resonance is substantially favored for the atoms with slow normal velocity, caused by their longer interaction time with the bichromatic laser field. As a result of the predominant contribution of these atoms, the observed linewidth of the EIT resonance is only $\ensuremath{\sim}9\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}$, which is more than ten times narrower than the inverse window-to-window flight time. In an external magnetic field, three and five EIT resonances have been observed for the vapor thickness of $L=2\ensuremath{\lambda}$, on

^{87}\mathrm{Rb}

and

^{85}\mathrm{Rb}

, respectively.