Stuttgart 2012 – wissenschaftliches Programm
Q 50.1: Vortrag
Donnerstag, 15. März 2012, 14:00–14:15, V7.03
Fibre-optical tweezers to preparate and interface single atoms — •Dominik Maxein, Sébastien Garcia, Leander Hohmann, Jakob Reichel, and Romain Long — Laboratoire Kastler Brossel UPMC ENS CNRS, 24 rue Lhomond, 75231 Paris Cedex 05
Preparing and manipulating single quantum objects is crucial to explore their interactions and to use them as components in quantum information processing. Atoms can be trapped in a focussed red-detuned laser beam forming an optical dipole trap or ``tweezers''. Sufficiently small tweezers exhibit the regime of collisional blockade, in which at most one atom stays trapped, making this an advantageous system to prepare single atomic qubits. However, the size and complexity of existing single-atom tweezers experiments impedes their highly desirable combination with other elements such as optical cavities.
Our approach is to simplify and miniaturize single-atom tweezers, turning them into a robust and versatile tool in quantum optics. This is achieved by using a single-mode fibre fixed to a small aspheric lens. This simple system serves the dual purpose of providing strongly focussed trapping light and collecting atomic fluorescence with high numerical aperture. A first implementation has been realized, and the obtained fluorescence signals clearly indicate the trapping of single atoms. We will study the properties of the system and furthermore characterize it as a single-photon source, expecting narrowband emission and good indistinguishability of successive photons. Finally, opportunities for continuing integration of fibre-optical single-atom tweezers and their combination with other experiments will be discussed.