Investigation On Electromagnetic Induced Grating Of Rubidium Atom And Its Applications

The interaction of photon and atom is a basic quantum physics system,which is easy to be manipulated.It is widely used in the many research fields,such as fundamental problems of quantum mechanics,quantum devices,quantum information processing,and precision measurement of basic physical constants.As one of basic research fields of quantum mechanics,quantum coherence has its physical phenomena such as electromagnetically induce transparency,vacuum induce transparency,optical bistable,optical switching,slowing of light speed and light storage.It is important for development of quantum information and quantum computing,and it also is a research hot issue in atomic,molecular and optical physics.When a weak probe field and a strong coupling field of traveling wave act on the medium,the medium is transparent to the weak probe radiation near the resonance position due to quantum coherence,this phenomenon is known as electromagnetically induce transparency(EIT).When the traveling wave field is replaced by the standing wave field,the absorption and dispersion of the medium are periodically modulated,the electromagnetically induced grating(EIG)is formed under the EIT mechanism.This grating has the optical properties of the conventional grating,and it is easy to realize the optical adjustment and dynamic reconstruction.EIG can be applied to quantum simulation,quantum physics and non-Hamilton physics.In this paper,we focused on the research of EIG of rubidium and its applications.The main research contents include three parts.1.The electromagnetically induced grating of three-level system is constructed using the density matrix theory.The analytical expressions of absorption and dispersion are obtained.The formation mechanism of different types of gratings such as amplitude grating,phase grating and hybrid grating is systematically studied.2.The electromagnetically induced grating is realized in the rubidium ladder three-level system.The distinct diffraction images of probe field are obtained in the experiment.The dependences on probe laser power,coupling laser power,the angle of two coupling lasers,two-photon detuning and atom temperature are studies in detail and the diffraction efficiency of first-order reached 25%.3.The electromagnetically induced Talbot effect is realized in the near field.The complete integer Talbot effect and clear fractional Talbot effect are observed.The experimental results agree well with the theoretical simulations.It is important for development of multi-parameter tunable and non-material grating.