The basics of single molecule spectroscopy will be addressed in this talk.  I will introduce an experiment in which a single dye

molecule is excited by a subwavelength aperture, located at the end of a metal-coated glass-fiber. This nanoscopic light source can be positioned in all three axes and can be approached with nanometer accuracy to the molecule, which is rigidly embedded in an organic crystal. Lifetime-limited transitions at optical frequencies can be reached, suppressing the molecule's dephasing processes by performing the experiment at 1.4 K.

The coherent response of the molecule is observed on the excitation beam and simultaenously by its red-shifted fluorescence. No noise-suppressing elements were used and the direct fingerprint on the excitation beam is recorded. The experimental results reveal an efficient coupling of the excitation light to the molecule.

PLEASE NOTE NON-STANDARD ROOM