Atom Trap Trace Analysis
- GEOPHYSICAL RESEARCH LETTERS, Vol. 41, 6758-6764, 2014, HD-KIP 14-96, 2014, GEOPHYSICAL RESEARCH LETTERS (41) 6758-6764
We report on the realization of Atom Trap Trace Analysis for 39Ar and its first application to dating of groundwater samples. The presented system achieves an atmospheric 39Ar count rate as high as 3.58 ± 0.10 atoms/h allowing for the determination of the 39Ar concentration in less than a day. We demonstrate that the measured count rates are proportional to the 39Ar concentration by intercomparison with Low-Level Counting results and by measurements on prepared argon samples with defined concentration. For a geophysical application, we degas three different groundwater samples and gas chromatographically extract the argon. The 39Ar ages inferred from the count rates extend over the accessible dating range and are in agreement with the Low-Level Counting results as well as with complementary isotope data.
- Nature Physics, 2011, doi:10.1038/nphys1961, HD-KIP 11-21, 2011, Nature Physics (doi:10.1038/)
In spontaneous emission an atom in an excited state undergoes a transition to the ground state and emits a single photon. Associated with the emission is a change of the atomic momentum due to photon recoil. Photon emission can be modified close to surfaces and in cavities. For an ion, localized in front of a mirror, coherence of the emitted resonance fluorescence has been reported. Previous experiments demonstrated that spontaneous emission destroys motional coherence. Here we report on motional coherence created by a single spontaneous emission event close to a mirror surface. The coherence in the free atomic motion is verified by atom interferometry. The photon can be regarded as a beamsplitter for an atomic matter-wave and consequently our experiment extends the original recoiling slit Gedanken experiment by Einstein to the case where the slit is in a robust coherent superposition of the two recoils associated with the two paths of the quanta.
- New Journal of Physics, Volume 12, HD-KIP 10-19, 2010, New Journal of Physics (12 065031) 15
We present our study of the realization of atom trap trace analysis for 39Ar, an ultra-sensitive detection method for rare isotopes based on laser cooling. We report on the experimental determination of the hyperfine spectrum of the relevant cooling transition. A high-intensity, optically collimated beam of metastable argon atoms has been set up, and fluorescence detection of single 40Ar atoms ina magneto-optical trap is realized. The deduced efficiencies of each stage lead to an expected 39Ar count rate of six atoms per hour in the final setup.