The Effect of an Interelectron Interaction on Electronic Properties in One-Dimensional Quasiperiodic Systems

The effect of an interelectron interaction ( U ) on electronic properties in one-dimensional quasiperiodic systems (the incommensurate Harper model and the Fibonacci model) is studied within the Hartree-Fock (HF) approximation. For the Fibonacci model, the HF one-body spectrum remains singular continuous (critical wave functions) for small | U |. For the Harper model, on the other hand, the singular continuous spectrum at critical coupling (λ c =2) disappears as soon as U is added.