A NUMERICAL STUDY OF THE QUANTUM OSCILLATIONS IN MULTIPLE DANGLING RINGS

We present the quantum mechanical calculations on the conductance of t he quantum waveguide topology containing multiply connected dangling m esoscopic rings with the transfer matrix approach. The profiles of the conductance as functions of the Fermi wave number of electrons depend on the number of rings and also on the geometric configuration of the system. The conductance spectrum of this system for disordered length s in the ring circumferences, dangling links, ballistic leads connecti ng consecutive dangling rings is examined in detail. We find that ther e exist two kinds of mini-bands, one originating from the eigenstates of the rings, i.e. the intrinsic mini-bands, and the extra mini-bands. Some of these extra minibands are associated with the dangling links connecting the rings to the main quantum wire, while others are from t he standing wave modes associated with the ballistic leads connecting adjacent dangling rings. These different kinds of mini-bands have comp letely different properties and respond differently to the geometric p arameter fluctuations. Unlike the system of potential scatterers, this system of geometric scatterers shows complete band formations at all energies even for finite number of scatterers present. There is a pref erential decay of the energy states, depending upon the type of disord er introduced. By controling the geometric parameters, the conductance band structure of such a model can be artificially tailored.