Abstract This paper presents a novel method for achieving parametric excitation in an optical polarization-modulated magneto-optical trap for a two-level atom. The proposed method has a unique mechanism that is different from that of the existing methods, which modulate the laser intensity, magnetic field gradient, or laser detuning, because the excitation realized through the polarization modulation originates from the competition between the repulsive and attractive forces on a two-level atom. The theoretical calculation is based on the simple Doppler cooling theory, and we derive atomic motion in a rotating frame and coupled equation for motional amplitude and phase, in detail. PACS numbers: 37.10.Vz, 37.10.De, 37.10.Gh
We report on magneto-optical trapping of fermionic
53Cr atoms. A Zeeman-slowed atomic beam provides loading rates up to $3\ifmmode\times\else\texttimes\fi{}{10}^{6}\phantom{\rule{0.3em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1}$. We present systematic characterization of the magneto-optical trap (MOT). We obtain up to $5\ifmmode\times\else\texttimes\fi{}{10}^{5}$ atoms in the steady-state MOT. The atoms radiatively decay from the excited
P state into metastable
D states, and, due to the large dipolar magnetic moment of chromium atoms in these states, they can remain magnetically trapped in the quadrupole field gradient of the MOT. We study the accumulation of metastable
53Cr atoms in this magnetic trap. We also report on the simultaneous magneto-optical trapping of bosonic
52Cr and fermionic
53Cr atoms. Finally, we characterize the light-assisted collision losses in this Bose-Fermi cold mixture.