An atomic beam of He in the metastable 2 3 S 1 state can be atomic-spin-polarised by Stern-Gerlach selection using a sextupole magnet. The authors report the first measurements of the polarisation obtained by this method. The authors have determined the metastable beam velocity distribution from a time-of-flight measurement. The distribution was found to be in the range of thermal velocities. The selection efficiency of the sextupole magnet was studied using a Stern-Gerlach deflection with an inhomogeneous dipole field. The experimental results give a vector polarisation close to 95%. Thus, the technique can be useful for many applications.An atomic beam of He in the metastable 2 3 S 1 state can be atomic-spin-polarised by Stern-Gerlach selection using a sextupole magnet. The authors report the first measurements of the polarisation obtained by this method. The authors have determined the metastable beam velocity distribution from a time-of-flight measurement. The distribution was found to be in the range of thermal velocities. The selection efficiency of the sextupole magnet was studied using a Stern-Gerlach deflection with an inhomogeneous dipole field. The experimental results give a vector polarisation close to 95%. Thus, the technique can be useful for many applications.

Journal of Physics E Scientific InstrumentsNov 1, 19841 citation

Velocity-selective electromagnetically-induced-transparency measurements of potassium Rydberg states

Wenchao Xu, Brian DeMarco

We demonstrate a velocity selection scheme that mitigates suppression of electromagnetically induced transparency (EIT) by Doppler shifts for coupling wavelengths larger than the probe wavelength. An optical pumping beam counterpropagating with the EIT probe beam transfers atoms between hyperfine states in a velocity-selective fashion. Measurement of the transmitted probe beam synchronous with chopping of the optical pumping beam enables a Doppler-free EIT signal to be detected. Transition frequencies between $5{P}_{1/2}$ and $n{S}_{1/2}$ states for $n=26$ , 27, and 28 in $^{39}\mathrm{K}$ are obtained via EIT spectroscopy in a heated vapor cell with a probe beam stabilized to the $4{S}_{1/2}\ensuremath{\rightarrow}5{P}_{1/2}$ transition. Using previous high-resolution measurements of the $4{S}_{1/2}\ensuremath{\rightarrow}n{S}_{1/2}$ transitions, we make a determination of the absolute frequency of the $4{S}_{1/2}\ensuremath{\rightarrow}5{P}_{1/2}$ transition. Our measurement is shifted by 560 MHz from the currently accepted value with a twofold improvement in uncertainty. These measurements will enable novel experiments with Rydberg-dressed ultracold Fermi gases composed of $^{40}\mathrm{K}$ atoms.We demonstrate a velocity selection scheme that mitigates suppression of electromagnetically induced transparency (EIT) by Doppler shifts for coupling wavelengths larger than the probe wavelength. An optical pumping beam counterpropagating with the EIT probe beam transfers atoms between hyperfine states in a velocity-selective fashion. Measurement of the transmitted probe beam synchronous with chopping of the optical pumping beam enables a Doppler-free EIT signal to be detected. Transition frequencies between $5{P}_{1/2}$ and $n{S}_{1/2}$ states for $n=26$, 27, and 28 in $^{39}\mathrm{K}$ are obtained via EIT spectroscopy in a heated vapor cell with a probe beam stabilized to the $4{S}_{1/2}\ensuremath{\rightarrow}5{P}_{1/2}$ transition. Using previous high-resolution measurements of the $4{S}_{1/2}\ensuremath{\rightarrow}n{S}_{1/2}$ transitions, we make a determination of the absolute frequency of the $4{S}_{1/2}\ensuremath{\rightarrow}5{P}_{1/2}$ transition. Our measurement is shifted by 560 MHz from the currently accepted value with a twofold improvement in uncertainty. These measurements will enable novel experiments with Rydberg-dressed ultracold Fermi gases composed of $^{40}\mathrm{K}$ atoms.

arXiv:1510.00368Physical Review AJan 4, 201621 citations

Velocity selection of atoms from beams by a Raman method

Eugeny Korsunsky, D. V. Kosachev, Boris G. Matisov +1 more

Mar 1, 19923 citations

Measurement of alkali-metal polarizabilities by deflection of a velocity-selected atomic beam

William Davis Hall, Jens C. Zorn

The electric dipole polarizability of the alkali-metal atoms Na, K, Rb, and Cs are determined by measuring the deflection of a velocity-selected beam by an inhomogeneous electric field. It is shown experimentally that scattering of slower beam atoms by background gas in the apparatus is an important systematic error in measurements of this kind if a beam-velocity selector is not used, and that this scattering is responsible for the discrepancies between different, earlier beam-deflection measurements of polarizability. The polarizability values obtained in this work are $\ensuremath{\alpha}(\mathrm{Na})=24.4\ifmmode\pm\else\textpm\fi{}1.7$ ${\mathrm{\AA{}}}^{3}$ , $\ensuremath{\alpha}(\mathrm{K})=45.2\ifmmode\pm\else\textpm\fi{}3.2$ ${\mathrm{\AA{}}}^{3}$ , $\ensuremath{\alpha}(\mathrm{Rb})=48.7\ifmmode\pm\else\textpm\fi{}3.4$ ${\mathrm{\AA{}}}^{3}$ , and $\ensuremath{\alpha}(\mathrm{Cs})=63.3\ifmmode\pm\else\textpm\fi{}4.6$ ${\mathrm{\AA{}}}^{3}$ .The electric dipole polarizability of the alkali-metal atoms Na, K, Rb, and Cs are determined by measuring the deflection of a velocity-selected beam by an inhomogeneous electric field. It is shown experimentally that scattering of slower beam atoms by background gas in the apparatus is an important systematic error in measurements of this kind if a beam-velocity selector is not used, and that this scattering is responsible for the discrepancies between different, earlier beam-deflection measurements of polarizability. The polarizability values obtained in this work are $\ensuremath{\alpha}(\mathrm{Na})=24.4\ifmmode\pm\else\textpm\fi{}1.7$ ${\mathrm{\AA{}}}^{3}$, $\ensuremath{\alpha}(\mathrm{K})=45.2\ifmmode\pm\else\textpm\fi{}3.2$ ${\mathrm{\AA{}}}^{3}$, $\ensuremath{\alpha}(\mathrm{Rb})=48.7\ifmmode\pm\else\textpm\fi{}3.4$ ${\mathrm{\AA{}}}^{3}$, and $\ensuremath{\alpha}(\mathrm{Cs})=63.3\ifmmode\pm\else\textpm\fi{}4.6$ ${\mathrm{\AA{}}}^{3}$.

Physical Review AOct 1, 1974103 citations

5{P}_{1/2}

and

n{S}_{1/2}

states for

n=26

, 27, and 28 in

^{39}\mathrm{K}

are obtained via EIT spectroscopy in a heated vapor cell with a probe beam stabilized to the $4{S}_{1/2}\ensuremath{\rightarrow}5{P}_{1/2}$ transition. Using previous high-resolution measurements of the $4{S}_{1/2}\ensuremath{\rightarrow}n{S}_{1/2}$ transitions, we make a determination of the absolute frequency of the $4{S}_{1/2}\ensuremath{\rightarrow}5{P}_{1/2}$ transition. Our measurement is shifted by 560 MHz from the currently accepted value with a twofold improvement in uncertainty. These measurements will enable novel experiments with Rydberg-dressed ultracold Fermi gases composed of

^{40}\mathrm{K}

atoms.

{\mathrm{\AA{}}}^{3}

, $\ensuremath{\alpha}(\mathrm{K})=45.2\ifmmode\pm\else\textpm\fi{}3.2$

{\mathrm{\AA{}}}^{3}

, $\ensuremath{\alpha}(\mathrm{Rb})=48.7\ifmmode\pm\else\textpm\fi{}3.4$

{\mathrm{\AA{}}}^{3}

, and $\ensuremath{\alpha}(\mathrm{Cs})=63.3\ifmmode\pm\else\textpm\fi{}4.6$

{\mathrm{\AA{}}}^{3}