Applying Electromagnetically Induced Transparency With Rydberg Atoms To Investigate Casimir-polder Effect

Rydberg atom has many prominent qualities,such as long spontaneous lifetime,high polarizability and strong transition dipole moment and so on.Dipole Blockade effect,which is caused by the interaction between Rydberg atoms,can be applied to not only construct qubit,but also investigate many body effect and nonlinear effect.Electromagnetically Induced Transparency(EIT)is a quantum interference effect,which is attributed to the interaction between atoms and coupling light and probe light,and on the resonance of probe light frequency,the absorption of probe light will disappear.Comparing with EIT of regular atoms,Rydberg EIT has a lot of special properties,for instance,creating non-classical light,cooperative effect,nonlinear absorption and so on.With the developing of integrated optics,we can operate atoms above the surface of solid device(atom chips).When atoms are tens of micros from the surface of solid device,Casimir-Polder(CP)effect,caused by electromagnetic fluctuation,will affect the properties of the energy level of atoms and further affect the transparent window of Rydberg EIT.This thesis studies Rydberg EIT in vacuum and near the surface of chips with different parameters.And we discuss the influence of the density and height of ensembles of atoms,principle quantum number and electromagnetic property of the chip material on Rydberg EIT.The results show that we can use Rydberg EIT to probe CP effect;conversely,CP effect can adjust Rydberg EIT.First of all,we review some basic properties of Rydberg atoms,and present how to compute dipole moment of Rydberg atoms in detail.Then we calculate stark effect of Rydberg atoms and interaction between Rydberg atoms and so on.Then,regarding Rydberg atom as two-level system,we simulate Dipole Blockade effect of Rydberg atoms by Monte Carlo method.Following that,we simulate Rydberg EIT,which the Rydberg interaction has been included.In high density situation,the energy of double population of Rydberg state will be shifted because of the interaction between Rydberg atoms,which will leads to the asymmetric line shape of the absorption;While in low density situation,the Rydberg EIT can be simplified to normal EIT due to the weak interaction between Rydberg atoms of which the distances are so large now.In the end,we probe the Rydberg EIT near the surface of atom chips,and discuss how different parameters,like the density of the ensemble of atoms,the height of the center of the ensemble of atoms and principal quantum number,affect EIT phenomenon.In low density condition,interaction between Rydberg atoms will not disturb Rydberg EIT to probe CP effect.The closer the Rydberg atoms are to the chip surface,the more prominent the CP effect will influence the transparency window of Rydberg EIT.With higher principle quantum number,the CP effect and interaction between Rydberg atoms will affect the transparency window of Rydberg EIT more saliently.We conclude that by choosing proper density,height and principal quantum number the CP effect can be shown from the change of Rydberg EIT,that is to say,Rydberg EIT can be used to probe CP effect.