Stationary light pulses in cold atoms at large optical depth

• Applicant: Professor Dr. Thomas Halfmann
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2010 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 179178351

Coherent interactions between light and quantum systems attracted increasing scientific interest in optical physics. Electromagnetically-induced transparency (EIT) exhibits a prominent example for such interactions. Recently, EIT was proposed to enable stationary light pulses (SLPs), i.e. light trapped in an “all-optical” cavity. SLPs permit applications in quantum information processing and related areas, e.g. to prepare entangled photons, BECs of polaritons, quantum interfaces, or “crystals” of photons, i.e. strongly correlated systems made of light. SLPs require atomic media at large optical depth. A recent technological attempt is based on loading of (cold) atoms into an optical trap inside a hollow-core fiber. However, the technology still suffers from small loading efficiencies and heating. The author proposes a modified setup, i.e. transfer of cold atoms from a non-spherical magneto-optical trap into the hollow-core fiber. The setup will provide very large optical depth, without heating of the atoms. This proposal deals with (i) implementation of the novel setup to provide cold atoms at large optical depth, (ii) preparation and investigation of SLPs, (iii) application of SLPs to provide a “crystal” of photons, and (iv) related investigations. Thus, the project aims at a combination of emerging technologies from the field of cold matter and novel concepts of quantum optics.

• DFG Programme: Research Grants