Silke Ospelkaus-Schwarzer is a German experimental physicist who studies ultra-cold molecular materials at the University of Hanover Institute of Quantum Optics. She was awarded a European Research Council Consolidator Award in 2022.

Early life and education

Ospelkaus studied physics at the University of Bonn. ^{[1] [2]} She moved to the University of Hamburg for her doctoral research, where she studied Fermi-Bose mixtures of potassium and rubidium in optical lattices. ^{[3] [4]} She was awarded the doctoral prize of the German Physical Society. ^[5] She moved to the JILA and the National Institute of Standards and Technology at the University of Colorado Boulder. ^{[2] [6] [7] [8]}

Research and career

In 2009, Ospelkaus returned to Germany, where she was made a group leader at the Max Planck Institute of Quantum Optics. She investigates the behaviour of atomic and molecular gases at ultra-cold temperatures. ^[9] In particular, ultra-cold molecular gases offer hope to better understand chemical processes. ^{[10] [5]} She has investigated two species atomic quantum gases mixtures, from which she can prepare polar molecules in a degenerate state.

By cooling hot samples of sodium and potassium, Ospelkaus is able to study exotic phenomena such as hyperfine ro-vibrational electronic interactions. She first combines Zeeman slowing with two-dimensional magneto-optical trapping, and once the atoms are cooled below the Doppler limit, loads them into a magnetic quadrupole trap. ^[11] At this stage, microwave evaporation cools the sodium, which results in the sympathetic cooling of potassium. At ≈ 10µK, interactions between the sodium and magnesium become increasingly strong, and further cooling demands more sophisticated tools. These include magnetic Feshbach resonance. ^{[11] [7]}

Ospelkaus has demonstrated laser cooling to study diatomic molecules. ^{[10] [12]} She achieves this cooling using direct laser cooling and buffer gas cooling. ^[13] Ultra-cold molecules are essentially stationary, which allows for their structure-property relationships to be studied at ultra-high precision. Dense gases of these molecules exhibit quantum behaviour, which allows for investigations into superconductivity. ^[13]

Ospelkaus uses molecular spectroscopy to understand the quantum states of alkali metal – alkaline earth metal atomic gases. ^[14] In 2022, she was awarded a European Research Council consolidator grant. ^[15]

Selected publications

• K-K Ni; S Ospelkaus; M H G de Miranda; et al. (18 September 2008). "A high phase-space-density gas of polar molecules". Science. 322 (5899): 231–235. arXiv: 0808.2963. doi: 10.1126/SCIENCE.1163861. ISSN  0036-8075. PMID  18801969. Wikidata  Q33370512.
• S Ospelkaus; K-K Ni; D Wang; et al. (1 February 2010). "Quantum-state controlled chemical reactions of ultracold potassium-rubidium molecules". Science. 327 (5967): 853–857. arXiv: 0912.3854. doi: 10.1126/SCIENCE.1184121. ISSN  0036-8075. PMID  20150499. Wikidata  Q59476983.
• K-K Ni; S Ospelkaus; D Wang; et al. (1 April 2010). "Dipolar collisions of polar molecules in the quantum regime". Nature. 464 (7293): 1324–1328. arXiv: 1001.2809. doi: 10.1038/NATURE08953. ISSN  1476-4687. PMID  20428166. Wikidata  Q59058301.

References