Effects Of Modulated Hopping On The Ground State Of 1D Correlated Electron System

In the one-dimensional strongly correlated electron system,the ground state phase diagram of the theoretical model shows the specific physical properties of the model,and it plays an important role in the study of condensed matter physics.In this thesis,by using the bosonization method and the renormalization group technique,at weak coupling and at half filling,we mainly modulate the kinetic energy terms of different models and analyze and compare the changes of the phase diagram.Firstly,We have constructed a theoretical model for one-dimensional inter acting electrons by modulating electronic kinetic hopping term on the basis of Hubbard mod-el.The paper proves that the electronic kinetic hopping term of the modulation Hubbard model changes the traditional ground state phase diagram,and also provides the possi-bility to realize triplet superconductivity.In the weak coupling region,the ground states of the model at half filling are:triplet superconducting order TS,singlet-superconducting order SS and SDW phase.In the ground state,the induced three-body gravity is the rea-son for the formation of the Luttinger Liquid(LL)phase with triplet superconductor order TS.Secondly,the extended Hubbard(t-U-V)model of one-dimensional correlation sys-tem is studied by introduced modulation parameter.This paper confirms that the induced three-body attraction changes topology of the conventional phase diagram.Besides the usual CDW and SDW phases,a BSDW phase exists for|U-2V|<8t?/?,In the ab-sence of V,an insulator-metal transition takes place,and the triplet superconductor order TS is realized for ?>(?).In addition,the general quantum phase diagram in-cluding insulating phase and superconducting correlation is also discussed.Similarly,We have modulated the kinetic energy term in the same way and have established a theoreti-cal model to study the controversial phase transition in the one-dimensional Penson-Kolb model.The ground state we found includes of three phases:a Luther-Emery(LE)phase with singlet-superconducting order SS,a LL phase with triplet superconductor order TS,and an insulating phase with bond-spin-density-wave(BSDW)correlation.A spin-gap transition into a ??-superconducting phase at | V |>t is briefly discussed.In this thesis,the model of one-dimensional electron-related interaction system is further studied,and we look at the effects of interactions in the model from another per-spective.It is proved that the kinetic energy transition term in the modulation model can change the ground-state phase diagram of the model.