Quantum oscillations in mesoscopic rings with many chains

We obtain exact analytical expressions for the electronic transport through a multichain system, also in the presence of magneto-and electrostatic fields. The geometrical structure of the electrodes is found to cause a splitting of the conduction band into many subbands depending on the number and the length of the chains, and the conductance approaches zero when the chain number is sufficiently large due to quantum interference. In the presence of a magnetic field very complicated oscillatory behavior of the conductance is found with a very sensitive dependence on the number of chains and their lengths, in a remarkable distinction from the usual two-chain Aharonov-Bohm (AB) ring. A transverse electric bias is found to cause oscillations of the conductance and by increasing the chain number the widths of the resonance peaks become narrower without a change of the oscillation periodicities. If electric and magnetic fields are simultaneously applied the magnetoconductance oscillation pattern depends sensitively on the bias. The present study may provide useful information for quantum device engineering.