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04.02.2016

Nils Trautmann
Technische Universität Darmstadt


Lecture Announcement 

Organiser:
Max Planck Institute for the Science of Light
Gerd Leuchs

Title:
Schemes for efficient matter field coupling on the single photon level

Speaker:
Nils Trautmann
Theoretical Quantum Physics Group
Institut für Angewandte Physik
Technische Universität Darmstadt

Time, place:

Thursday, February 4, 2016, 10:30 a.m.
Large seminar room (429/435), Bau 24, Guenther-Scharowsky-Str. 1

Abstract:
The ability to couple single photons efficiently to single material
quantum systems, such as atoms or ions, is a key ingredient for quantum
information processing. In the first part of the talk, we discuss the
influence of the center of mass motion of a trapped two level system on
efficient resonant single photon absorption in free space. The center of
mass motion can lead to a severe reduction of the coupling efficiency in
current experimental implementations.
It is demonstrated that the time dependent modulation of the harmonic
trapping frequency allows to squeeze the two level system’s center of
mass motion so strongly that almost perfect single photon absorption is
possible even in cases of weak confinement by a trapping potential.
In the second part of the talk, a scheme for triggering a dissipation
dominated highly efficient excitation transfer from a single photon wave
packet, with quite arbitrary shape to a single quantum emitter, is
presented.
Our scheme does not require additional laser pulses or quantum feedback
and is not restricted to highly mode selective cavity quantum
electrodynamical architectures. We demonstrate the usefulness of our
scheme for building a deterministic quantum memory and a deterministic
frequency converter between photonic qubits of different wavelengths.