Super-resolution measurements related to uncertainty relations in optical and biological fluorescence systems

Abstract

Super-resolution effects in optical and fluorescence biological systems are analyzed and their relations with uncertainty relations are discussed. Super-resolutions obtained in the optical systems, including especially NSOM, SIM and hyperlens, are related to an increase of the spatial frequencies in the object plane leading to very small effective wavelengths and thus the resolution is increased far beyond the Abbe limit. Super-resolution measurements obtained in the fluorescent biological systems STED, FPALM and RESOLFT are treated. An example of a four-level STED system is analyzed in analogy to a four-level laser system, but the special space dependence of the STED light is taken into account, restricting the fluorescence from extremely small volume, and thus extremely high resolution is obtained. Localization of individual molecules is described by the FPALM method where interference between coherent fluorescent photons is taken into account. While in the STED method very high laser intensities are needed in its variant method known as RESOLFT the super-resolution measurements can be obtained by much weaker light intensities. This new method is analyzed and the reasons for a such large reduction in light intensities are explained.