A COHERENT POPULATION TRAPPING IN QUANTUM-SYSTEMS

A coherent population trapping (CPT) is a recently developed tool for high resolution spectroscopy. This method is based on a nonlinear coherent interaction between the atomic system and the electromagnetic radiation falling upon and a registration of medium responses for a subsequent analysis of their fine structure which contains information about spectral characteristics of a quantum system. The principal physics features of a CPT are considered. Effects of relaxation and atomic levels structure and also external factors on dynamics and characteristics of CPT have been investigated. The results of experimental studies on CPT are represented. They confirm theoretical framework ideas to be adequate to a real physical process. The possibility of CPT employments in a frequency stabilization, laser cooling and so on are examined.