Quantum Manipulation In A Multi-level Atomic System

Quantum interference in quantum optics has been discussed extensively recently, many interesting phenomena have been observed due to quantum interference among multi-channels in multilevel atomic systems. On the other hand, as a new branch of science and technology, quantum manipulation is very active these years. Its development may change computer, medical science, chemistry and life sciences, etc. thoroughly, thus make human life change tremendously. At present, the study focus of quantum manipulation is physical realization, and the research of the quantum control system is also mainly in the stage of theoretical exploring. In this thesis, by means of quantum optics theory, we have intensively investigated the problem theoretically, and a series of meaningful results are obtained.Quantum interference is very different from the classical interference, which breaks through the traditional bottleneck while leading into the superposition principle in quantum mechanics, it makes important progress in many fields especially in quantum information, quantum communication encryption and light quantum computer, etc. This thesis is based on the National Natural Science Foundation of China "a relevant study of the new mechanism on lasing in random media" and "syudy of the new mechanism on single photo laser", we have further studied many kinds of quantum manipulation phenomena on the basis of quantum interference. The key points of this thesis are presented as follows:1. Overview the tendency of the quantum interference and quantum manipulation.2. Making an analysis of relevant research approaches, tool foundations of the theory included wave function, quantum dipole, theory of density matrix, non-linear optic polarizabilty several kinds of basic representation and Semi-classical Theory and quantum theory.3.Study under the quantum manipulation on the base of the quantum effects of a tripod-type four-level atom system interacting with three light fileds ,there is a phenomenon of electromagnetic induction transparent in resonance-near resonance case, have appeared optical switching effect. Under the electromagnetism inducement of quantum interference, left handedness carry out on the weak probe field, and have compare pump field,probe field,control field intensity effect on the left handedness.4.the electromagnetically inductive left-handedness in a four-level atomic system associated with a pair of upper excited hyperfine levels has been investigated. The properties of left-handedness with vacuum-induced coherence arising from the cross coupling spontaneous emission pathways have also been discussed.This project is supported by the National Natural Science Foundation of China (Grant No.No. 60278016,No.60768001)...