TUNNELING INTO A 2-DIMENSIONAL ELECTRON-SYSTEM IN A STRONG MAGNETIC-FIELD

We investigate the properties of the one-electron Green's function in an interacting two-dimensional electron system in a strong magnetic fi eld, which describes an electron tunneling into such a system. From fi nite-size diagonalization, we find that its spectral weight is suppres sed near zero energy, reaches a maximum at an energy of about 0.2e2/ep silonl(c), and decays exponentially at higher energies. We propose a t heoretical model to account for the low-energy behavior. For the case of Coulomb interactions between the electrons, at even-denominator fil ling factors such as nu = 1/2, we predict that the spectral weight var ies as e(-omega0/Absolute value of omega), for omega --> 0.