Detection of Dark-State Relaxation through Twodimensional Nanooptical Spectroscopy

摘要

The correct understanding of the electronic structure and relaxation behavior in nanosystems is essential for technical applications. We propose a spectroscopic method to measure the dipole-forbidden electronic transitions of quantum dots and trace their relaxation behavior. Therefore, we utilize two-dimensional coherent spectroscopy, which is an advantageous tool to get information about the dynamics of exciton densities and coherences in nanoscopic structures. In combination with nanoplasmonics, it enables excitation of dipole-forbidden states. A nanoplasmonic dolmen structure allows us to dynamically excite either dipole-allowed and dipole forbidden states selectively. In combination with two-dimensional spectroscopy, this gives us additional control over excitation and tracing relaxation involving dipole-forbidden states in nanoscopic systems.