Collective dynamics of the electron gas in an anharmonic quantum well

Abstract

Within a quantum hydrodynamic model and using a variational method, the collective dynamics of the electron gas with the exchange-correlation effect in an anharmonic quantum well are studied both analytically and numerically. The two collective excitation modes, i.e. the dipole mode and the breather mode, are obtained analytically. The frequency shift induced by the exchange correlation, and the periodic collapse revival of the collective dynamics of the electron gas originating from nonlinear coupling between the two modes, are discussed. We found that the anharmonicity and the exchange-correlation effect are coupled, and the frequency shift and the collapse revival of the collective excitations depend strongly on the number of particles, the anharmonicity, and the quantum and exchange-correlation effects.