Quantum-memory-assisted Atomic Entropy Uncertainty In Dicke Model

The investigation of entropic uncertainty principle is a hot topic in quan-tum optics and quantum information. Recently, important advances on entropic uncertainty principle have been made internationally. One of them is the quantum-memory-assisted entropy uncertainty principle proposed by Rense et al which shows that the quantum information stored in quantum memory systems is able to reduce or eliminate the quantum uncertainty of the system to be measured. In the thesis, the quantum-memory-assisted entropy uncertainty of Dicke model under the Markovian and non-Markovian environment is investigated by using the quantum-memory-assisted entropy uncertainty principle and the theory of open quantum systems, and innovative results are gained. This article is organized as follows.In chapter1, the history of entropy, the basic definitions of entropy in both classical and quantum information theory are presented followed by the Heisen-berg’s uncertainty principle, the entropy uncertainty principle and the quantum-memory-assisted entropy uncertainty.In chapter2, the Markovian approximation and the the Markovian quantum master equation are briefly introduced. Synchronously, the non-Markovian ap-proximation and the the non-Markovian quantum master equation are given out. Then, the Dicke model is introduced. The exact solution of the Dicke model is gained by using the time-convolutionless projection operator technique, and the result is expanded to two-atom system.In chapter3, the quantum-memory-assisted atomic entropic uncertainty of Dicke model with a classical driving field is discussed. The influences of non-Markovian effect, the classical driving field and the detuning of the system on entropic uncertainty are examined. The dynamics of entropic uncertainty is ex-plained by the memory effects of the non-Markovian processes. The thesis shows that entropic uncertainty could be greatly reduced by the effects of the non-Markovian processes, classical field and the detuning of the system.In chapter4, the summary and the outlook of the thesis are presented.