Stuttgart 2012 – wissenschaftliches Programm
Q 34.36: Poster
Dienstag, 13. März 2012, 16:30–19:00, Poster.I+II
Nonlinear Interaction Between Light Pulses Mediated by Four-Wave Mixing of Matter Waves — •Simon Baur, Stefan Riedl, Christoph Vo, Matthias Lettner, Gerhard Rempe, and Stephan Dürr — Max-Planck-Institute of Quantum Optics, Hans-Kopfermann-Str. 1, 85748 Garching
Coherent nonlinear interaction of weak light pulses is an important goal with various applications in quantum information processing and quantum metrology. Here we experimentally demonstrate a scheme where two weak light pulses propagating in two different momentum modes are stored as matter waves in a BEC of 87Rb atoms using a Raman process. Due to atomic four-wave mixing of matter waves, an initially empty atomic momentum mode is populated. Finally all matter waves are converted back into light pulses. In this process, the new matter wave mode creates population in a light mode that was originally empty. In addition, we observe high contrast interference fringes in the read-out light as a function of the duration of the four-wave mixing. This shows that all involved processes, including the four-wave-mixing, are phase coherent. A novel conceptual aspect of our work is that it avoids the inherent need for high intensities in nonlinear optics by temporarily converting light into matter waves and making use of strong atom-atom interactions.