Quantum optics with metastable helium atoms

We simultaneously confine fermionic metastable $^{3}\mathrm{H}\mathrm{e}$ atoms and bosonic metastable $^{4}\mathrm{H}\mathrm{e}$ atoms in a magneto-optical trap. The trapped clouds, containing up to $1.5\ifmmode\times\else\texttimes\fi{}{10}^{8}$ atoms of each isotope, are characterized by measuring ions and metastable helium atoms escaping from the trap. Optical pumping of $^{3}\mathrm{H}\mathrm{e}$ atoms to a nontrapped hyperfine state is investigated and it is shown that large atom numbers can be confined without additional repumping lasers. Unique possibilities for quantum degeneracy experiments with mixtures of spin-polarized metastable $^{3}\mathrm{H}\mathrm{e}$ and $^{4}\mathrm{H}\mathrm{e}$ atoms are indicated.We simultaneously confine fermionic metastable $^{3}\mathrm{H}\mathrm{e}$ atoms and bosonic metastable $^{4}\mathrm{H}\mathrm{e}$ atoms in a magneto-optical trap. The trapped clouds, containing up to $1.5\ifmmode\times\else\texttimes\fi{}{10}^{8}$ atoms of each isotope, are characterized by measuring ions and metastable helium atoms escaping from the trap. Optical pumping of $^{3}\mathrm{H}\mathrm{e}$ atoms to a nontrapped hyperfine state is investigated and it is shown that large atom numbers can be confined without additional repumping lasers. Unique possibilities for quantum degeneracy experiments with mixtures of spin-polarized metastable $^{3}\mathrm{H}\mathrm{e}$ and $^{4}\mathrm{H}\mathrm{e}$ atoms are indicated.

Physical Review LettersJul 27, 200426 citations

Trapping fermionic and bosonic helium atoms

R. J. W. Stas

This thesis presents experimental and theoretical work performed at the Laser Centre of the Vrije Universiteit in Amsterdam to study laser-cooled metastable triplet helium atoms. Samples containing about 3x10^8 helium atoms-either fermionic helium-3 atoms, bosonic helium-4 atoms or mixtures thereof-are cooled to a temperature around 1 mK and form the starting point of the presented studies. The studies include an investigation of cold ionizing collisions in the absence of resonant light, an investigation of magneto-optical trapping with ultraviolet light, a feasibility study of an atomic fountain clock based on metastable helium-3 atoms and the first demonstration of magneto-optical trapping of an isotopic mixture of metastable helium atoms.This thesis presents experimental and theoretical work performed at the Laser Centre of the Vrije Universiteit in Amsterdam to study laser-cooled metastable triplet helium atoms. Samples containing about 3x10^8 helium atoms-either fermionic helium-3 atoms, bosonic helium-4 atoms or mixtures thereof-are cooled to a temperature around 1 mK and form the starting point of the presented studies. The studies include an investigation of cold ionizing collisions in the absence of resonant light, an investigation of magneto-optical trapping with ultraviolet light, a feasibility study of an atomic fountain clock based on metastable helium-3 atoms and the first demonstration of magneto-optical trapping of an isotopic mixture of metastable helium atoms.

Jun 1, 20051 citation

We simultaneously confine fermionic metastable

^{3}\mathrm{H}\mathrm{e}

atoms and bosonic metastable

^{4}\mathrm{H}\mathrm{e}

atoms in a magneto-optical trap. The trapped clouds, containing up to $1.5\ifmmode\times\else\texttimes\fi{}{10}^{8}$ atoms of each isotope, are characterized by measuring ions and metastable helium atoms escaping from the trap. Optical pumping of

^{3}\mathrm{H}\mathrm{e}

atoms to a nontrapped hyperfine state is investigated and it is shown that large atom numbers can be confined without additional repumping lasers. Unique possibilities for quantum degeneracy experiments with mixtures of spin-polarized metastable

^{3}\mathrm{H}\mathrm{e}

and

^{4}\mathrm{H}\mathrm{e}

atoms are indicated.