Quantum and nonlinear optics with surface plasmons

• Applicant: Professor Dr. Dirk Witthaut
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2008 to 2011
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 62605028

The last decades have seen an enormous progress in the control of matter on scales governed by the laws of quantum mechanics. Nowadays it is possible to trap and manipulate single atoms using laser light. On the other hand one can create, detect and even store single photons. A missing link is the interaction of single photons with single atoms, which would open the door for fundamentally new applications.However, the coupling of a single photon to a single atom is usually extremely weak, preventing an efficient interaction. It can be strongly enhanced by confining the light wave to a very small volume. A common but challenging approach uses the confinement in a resonator between two mirrors. Recently it has been proposed to use the surface-plasmon modes instead, where a light wave travels at the surface of a metallic nanowire. The confinement at the surface leads to the desired strong coupling to a single atom.In this project we want to lay the theoretical foundations for potential applications of this method. We will work out the design of actual devices for the use in quantum information science in a close collaboration with two experimental groups. Furthermore we will investigate the stability against perturbations from the environment and analyze the transition from quantum to classical nonlinear optics for large photon numbers.

• DFG Programme: Research Fellowships
• International Connection: Denmark
• Host: Professor Dr. Anders S. Sorensen