Two-dimensional model for the cold atom micromaser

Poster (2004)

Detuning effects on the mazer

in Physicalia Magazine (2003), 25

A short review of the theoretical studies of the cold atom micromaser (mazer) is presented. Existing models are then improved by considering more general working conditions. Especially, the mazer physics ... [more ▼]

A short review of the theoretical studies of the cold atom micromaser (mazer) is presented. Existing models are then improved by considering more general working conditions. Especially, the mazer physics is investigated in the situation where a detuning between the cavity mode and the atomic transition frequency is present. Interesting new effects are pointed out. Especially, it is shown that the cavity may slow down or speed up the atoms according to the sign of the detuning and that the induced emission process may be completely blocked by use of a positive detuning. The transmission probability of ultracold atoms through a micromaser is also studied and we generalize previous results established in the resonant case. In particular, it is shown that the velocity selection of cold atoms passing through the micromaser can be very easily tuned and enhanced using a nonresonant field inside the cavity. [less ▲]

1s2s2p(2)3s 6P - 1s2p(3)3s 6S° transitions in OIV

in Physical Review. A (2003), 67

The energies and lifetimes of doubly excited sextet states of boron-like O IV, F V, and Ne VI are calculated with the multiconfiguration Hartree-Fock approach, including QED and higher-order corrections ... [more ▼]

The energies and lifetimes of doubly excited sextet states of boron-like O IV, F V, and Ne VI are calculated with the multiconfiguration Hartree-Fock approach, including QED and higher-order corrections, and also with the multiconfiguration Dirac-Fock GRASP code. The wavelengths and transition rates of electric-dipole transitions from the inner-shell excited terms 1s2s2p23s 6P–1s2p33s 6So are investigated by beam-foil spectroscopy in the XUV spectral region. The predicted transition wavelengths agree with the experiment. The higherorder corrections, fine structures, and spectrum with high wavelength resolution are found to be critically important in these comparisons. Nine new lines have been identified. The ground sextet states of boronlike atoms are metastable and well above several ionization levels. These are possible candidates for XUV and soft x-ray lasers. [less ▲]

The mazer physics

Conference (2003)

The cold atom micromaser in a vertical configuration

Poster (2003)

Detuning effects in the one-photon mazer

Poster (2002)

Detuning effects in the one-photon mazer

Poster (2002)

Radiative lifetime measurements in Tm III with time-resolved laser spectroscopy and comparisons with HFR calculations

in Journal of Physics : B Atomic Molecular & Optical Physics (2001), 34

Natural radiative lifetimes of eight levels in Tm III were measured with the time-resolved laser-induced fluorescence (LIF) technique. Free doubly ionized thulium ions were obtained in a laser-produced ... [more ▼]

Natural radiative lifetimes of eight levels in Tm III were measured with the time-resolved laser-induced fluorescence (LIF) technique. Free doubly ionized thulium ions were obtained in a laser-produced plasma. Three even-parity levels were excited from the ground state with one-photon excitation, using a laser system generating pulses of 1 ns duration. Five odd-parity levels were excited from the ground state with two-photon excitation, where a picosecond laser system was employed. In both cases, the lifetimes were evaluated from transient LIF signals detected with a fast-detection system. The experimental lifetime results were compared with Hartree–Fock calculations including relativistic corrections. Good agreement was achieved for the 4f126p levels while larger discrepancies are noted for some 4f125d levels. [less ▲]

Singlet-triplet excitation ratios in Ne III, Ar III and N II under ion impact

in European Physical Journal D -- Atoms, Molecules, Clusters & Optical Physics (2001), 15

Peculiar properties of ion-atom collision systems, in particular deviations from statistical populations of singlet and triplet levels, can be studied by optical spectroscopy.We have extended earlier ... [more ▼]

Peculiar properties of ion-atom collision systems, in particular deviations from statistical populations of singlet and triplet levels, can be studied by optical spectroscopy.We have extended earlier studies by VUV spectroscopy of a number of collision systems at various collision energies in the 0.01-MeV/nucleon to 1-MeV/nucleon range, involving H+ 2 , H+, He+, He2+, Ne+, Ar+, and N+ 2 as projectiles and Ne, Ar, and N2 as target gases. Statistically signi cant deviations of the relative intensities of singlet and triplet lines from simple ratios are observed in the displaced terms of the valence shell of Ne III, corroborating and extending earlier work. For Ar III, the energy dependences of singlet-to-triplet excitation ratios are very different for dff erent projectiles. For NII, in contrast, all observed line ratios are practically independent of the projectile energy. [less ▲]

Beam-gas excitation of Ar III 3s3p5 singlet and triplet terms

Poster (2001)