Operation Principles and Applications of Ultra-Sensitive Optical Detectors at Nanoscale: Facts and Artifacts

Measurements on a nanoscale are at technological limits in several factors and therefore are more complex than measurements on a macro-scale. The required sensitivity and precision critically depends on the factors which may be marginal in conventional measurements. We describe phenomena observed in scientific CMOS cameras at the level of several photoelectrons per pixel and the effect of the local refractive index on the radiative and nonradiative transition rates.