Effects of correlation on the structure of impurity bands /

The effects of electron-electron interaction on the electronic density of states has been considered for a dilute system of scattering centers distributed randomly in an electron gas of moderate density. Using as the starting point an independent-electron t-matrix method, a modified t-matrix in the presence of the electron-electron interaction is obtained. To illustrate the effects of correlation, the formalism has been applied to the simple case of a linear chain of attractive 6-function potentials distributed randomly. The electrons are assumed to interact by means of a repulsive 6-function potential. The density of states in the impurity band is evaluated and compared with the results for independent electrons. It is found that the inclusion of electron-electron interaction produces a significant broadening and downward energy shift of the impurity band.Includes bibliographical references (p. 14-15).The effects of electron-electron interaction on the electronic density of states has been considered for a dilute system of scattering centers distributed randomly in an electron gas of moderate density. Using as the starting point an independent-electron t-matrix method, a modified t-matrix in the presence of the electron-electron interaction is obtained. To illustrate the effects of correlation, the formalism has been applied to the simple case of a linear chain of attractive 6-function potentials distributed randomly. The electrons are assumed to interact by means of a repulsive 6-function potential. The density of states in the impurity band is evaluated and compared with the results for independent electrons. It is found that the inclusion of electron-electron interaction produces a significant broadening and downward energy shift of the impurity band.Mode of access: Internet