High Resolution Microscopy on a Single Molecule: From Near-Field Effects to Quantum OpticsIlja Gerhardt Single dye molecules at cryogenic temperatures exhibit many spectroscopic phenomena known from the study of free atoms and are thus promising candidates for experiments in fundamental quantum optics. However, the past techniques for their detection have either sacrificed information on the coherence of the excited state or have been inefficient. We are able to show that these problems can be addressed by near-field experiments at cryogenic temperatures [1] of by focusing the excitation light near to the extinction cross-section of a molecule [2]. These experiments show that a substantial fraction of light might be extinct by a molecule in front of an aperture of a near-field tip. In follow-up experiments using a solid immersion lens, we were able to observe quantum optical phenomena like the Mollow-Triplet and Rabi oscillations [2,3]. The observed coherent phenomena allow a higher localization accuracy for a single emitter than classical methods. I will present a proof-of-principal optical far-field experiment which shows sub wavelength optical response, smaller than \lambda /10. [1] I. Gerhardt, G. Wrigge, P. Bushev, G. Zumofen, M. Agio, R. Pfab, V. Sandoghdar, Strong Extinction of a Laser Beam by a Single Molecule, Physical Review Letters, 2007, 98, 4 [2] G. Wrigge, I. Gerhardt, J. Hwang, G. Zumofen, V. Sandoghdar, Efficient coupling of photons to a single molecule and the observation of its resonance fluorescence, Nature Physics, 2008, 4, 60-66 [3] I. Gerhardt, G. Wrigge, G. Zumofen, J. Hwang, A. Renn, V. Sandoghdar, Coherent state preparation and observation of Rabi oscillations in a single molecule, Physical Review A, 2009, 79, 4 |