The Property Of The Berry Phase In The Metal-semiconductor Nanocrystal Complexes

The hybrid nanocrystal complex composed of the metal nanoparticle(MNP)and the semiconductor quantum dot(SQD) draws more attention to be researched,because coupled interactions between the excitons from the SQD and the plas-mons of the MNP show novel effects, which lead to generate new physical phe-nomena. Our work is to investigate the interaction in the nanocrystal complexes and the properties of Berry phase in the nanocrystal complexes.The first chapter is a review,introducing the research background and the pri-mary research contents.The second chapter gives the basic theories related to the research contents.We present the motion equation of the density matrix and the calculation of the Berry phase in the basic structure, which is beneficial to the following theoreticalcalculation.In the third chapter, we discuss the interaction in the nanocrystal complexes composed of a MNP and a SQD for special configuration and general configura-tion, respectively. Based on the former nanocrystal complexes, we investigate the interaction in the system composed of a MNP and two SQDs for special configu ration and general configuration, respectively. In contrast to the fixed structure in a row, this system allows the SQDs locating above the metal nanoparticle with an arbitrary angle and the same distance from the MNP. Through exactly solving the electric field analytically, the coupled interactions and Hamiltonian are explicitly expressed. The results are beneficial to the further study on the similar system.The fourth chapter is the primary part,and our innovation point is also pre-sented in the chapter. We investigate the Berry phase of the nanocrystal complexes made of SQD and MNP. In our designed structure of the SQD rotating around the MNP slowly excited by the circular polarized light, we calculate the Berry phase through analyzing the electric field with the solving the Laplace equation and the optical Bloch equations. Numerical results show the relation between the Berry phase and the interparticle distance, as well as the interparticle angle. Based on our theory, we acquire the Berry phase in the nanocrystal complexes through the method of polarization interference, which is useful to observe the Berry phase in the nanocrystal complexes experimentally. We can observe the dipole-dipole in-teraction easily via the Berry phase, which is helpful to design the well-performed optical sensor and switch based on the mechanism.The last chapter is the summary.