Resonance Energy Transfer

Resonance energy transfer, also known as Förster- or fluorescence- resonance energy transfer, or electronic energy transfer, is a photonic process whose relevance in many major areas of science is reflected both by a wide prevalence of the effect and through numerous technical applications. The process, operating through an optical near-field mechanism, effects a transport of electronic excitation between physically distinct atomic or molecular components, based on transition dipole-dipole coupling. In this chapter a comprehensive survey of the process is presented, beginning with an outline
of the history and highlighting the early contributions of Perrin and Förster. A review of the photophysics behind resonance energy transfer follows, and then a discussion of some prominent applications of resonance energy transfer. Particular emphasis is given to analysis and sensing techniques used in molecular biology, ranging from the ‘spectroscopic ruler’ measurements of functional group separation, to fluorescence lifetime microscopy. The chapter ends with a description of the role of energy transfer in photosynthetic light harvesting.