Laser cooling of europium atoms

We demonstrate laser cooling and magneto-optical trapping of europium. The atoms are optically pumped to a metastable state and then loaded from an atomic-beam source via conventional Zeeman slowing and magneto-optical trapping techniques using a $J=13/2\ensuremath{\leftrightarrow}J=15/2$ quasicyclic transition. The trapped populations contained up to $1\ifmmode\times\else\texttimes\fi{}{10}^{7}$ atoms, and a two-body loss rate is estimated as $1\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}10}\phantom{\rule{0.28em}{0ex}}{\mathrm{cm}}^{3}/\mathrm{s}$ from the nonexponential loss of atoms at high densities. We also observed leakage out of the quasicyclic transition to the two metastable states with $J=9/2$ and $11/2$ , which is adequate to pump the laser-cooled atoms back to the $J=7/2$ ground state.We demonstrate laser cooling and magneto-optical trapping of europium. The atoms are optically pumped to a metastable state and then loaded from an atomic-beam source via conventional Zeeman slowing and magneto-optical trapping techniques using a $J=13/2\ensuremath{\leftrightarrow}J=15/2$ quasicyclic transition. The trapped populations contained up to $1\ifmmode\times\else\texttimes\fi{}{10}^{7}$ atoms, and a two-body loss rate is estimated as $1\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}10}\phantom{\rule{0.28em}{0ex}}{\mathrm{cm}}^{3}/\mathrm{s}$ from the nonexponential loss of atoms at high densities. We also observed leakage out of the quasicyclic transition to the two metastable states with $J=9/2$ and $11/2$, which is adequate to pump the laser-cooled atoms back to the $J=7/2$ ground state.

arXiv:1803.06475Physical Review AJun 18, 201823 citations

Magnetic trap of metastable europium atoms

Hiroki Matsui, Yuki Miyazawa, Ryotaro Inoue +1 more

We report the measurement of one-body loss rates for magnetically trapped metastable europium atoms and the study of their loss mechanism. The loss of atoms observed in a magneto-optical trap is not fully understood because of the indivisibility of the loss regarding optical pumpings due to the presence of cooling laser beams. We magnetically trap the atoms by directly loading from the magneto-optical trap and observe almost identical one-body loss rates of approximately $2.6\,\mathrm{s^{-1}}$ for two isotopes: $\mathrm{{}^{151}Eu}$ and $\mathrm{{}^{153}Eu}$ . Our rate-equation-based model, combined with loss rate measurements carried out with repumpers, shows that blackbody radiation at room temperature drives E1 transitions and induces the observed losses.We report the measurement of one-body loss rates for magnetically trapped metastable europium atoms and the study of their loss mechanism. The loss of atoms observed in a magneto-optical trap is not fully understood because of the indivisibility of the loss regarding optical pumpings due to the presence of cooling laser beams. We magnetically trap the atoms by directly loading from the magneto-optical trap and observe almost identical one-body loss rates of approximately $2.6\,\mathrm{s^{-1}}$ for two isotopes: $\mathrm{{}^{151}Eu}$ and $\mathrm{{}^{153}Eu}$. Our rate-equation-based model, combined with loss rate measurements carried out with repumpers, shows that blackbody radiation at room temperature drives E1 transitions and induces the observed losses.

Apr 28, 20210 citations

Laser Cooling of Atoms

Hidekazu Hachisu

Nihon Kikai Gakkaishi/Journal of the Japan Society of Mechanical EngineersJan 1, 20090 citations

Narrow-line magneto-optical trap for europium

Yuki Miyazawa, Ryotaro Inoue, Hiroki Matsui +2 more

We report on the realization of a magneto-optical trap (MOT) for europium atoms using a narrow-line cooling transition with a natural linewidth of 97 kHz. Europium is a strongly dipolar species with interesting properties, such as the presence of hyperfine structure and the absence of electronic orbital angular momentum. Our starting point of the MOT is continuous capturing and cooling of optically pumped metastable europium atoms. We have employed simultaneous MOT for the metastable and ground-state atoms. The trapped metastable atoms are successively pumped back to the ground state and then continuously loaded to the narrow-line MOT, where up to $4.7\ifmmode\times\else\texttimes\fi{}{10}^{7}$ atoms are captured. A spin-polarized sample at a temperature of $6\phantom{\rule{0.16em}{0ex}}\ensuremath{\mu}\mathrm{K}$ and with a peak number density of $2.2\ifmmode\times\else\texttimes\fi{}{10}^{11}\phantom{\rule{0.16em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}3}$ is obtained through the compression process, resulting in a phase space density of $3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$.We report on the realization of a magneto-optical trap (MOT) for europium atoms using a narrow-line cooling transition with a natural linewidth of 97 kHz. Europium is a strongly dipolar species with interesting properties, such as the presence of hyperfine structure and the absence of electronic orbital angular momentum. Our starting point of the MOT is continuous capturing and cooling of optically pumped metastable europium atoms. We have employed simultaneous MOT for the metastable and ground-state atoms. The trapped metastable atoms are successively pumped back to the ground state and then continuously loaded to the narrow-line MOT, where up to $4.7\ifmmode\times\else\texttimes\fi{}{10}^{7}$ atoms are captured. A spin-polarized sample at a temperature of $6\phantom{\rule{0.16em}{0ex}}\ensuremath{\mu}\mathrm{K}$ and with a peak number density of $2.2\ifmmode\times\else\texttimes\fi{}{10}^{11}\phantom{\rule{0.16em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}3}$ is obtained through the compression process, resulting in a phase space density of $3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$.

arXiv:2102.11700Physical Review AMay 26, 202118 citations

Laser Cooling of Atoms and Ions

F. G. Major

Springer eBooksJan 1, 20072 citations

J=9/2

and

11/2

, which is adequate to pump the laser-cooled atoms back to the

J=7/2

ground state.

2.6\,\mathrm{s^{-1}}

for two isotopes:

\mathrm{{}^{151}Eu}

and

\mathrm{{}^{153}Eu}

. Our rate-equation-based model, combined with loss rate measurements carried out with repumpers, shows that blackbody radiation at room temperature drives E1 transitions and induces the observed losses.