ELECTRONIC-STRUCTURE AND HEAT-CAPACITY OF MULTIQUANTUM-WELL STRUCTURES IN STRONG MAGNETIC-FIELDS

Abstract

We study the electronic structure and the heat capacity in AlGaAs-GaAs multi-quantum well structures for up to 5 wells in the presence of strong magnetic fields. Using rectangular potential wells, the effects of the interactions between the adjacent wells and the magnetoelectric confinement on the energy level and the energy level and the heat capacity are examined. We find strongly oscillating heat capacities which consist of the intralevel and interlevel contributions. The interlevel peaks in the oscillating heat capacity are found at the filling factor, v=N(w)m, where N-w is the number of wells and m is a positive integer. In each branch of the Landau fan of the multi-quantum well structures the energy levels in tilted magnetic fields are found to be unequally spaced due to a coupling term in the Hamiltonian. The dependences of the asymmetric shape of intralevel peaks in heat capacity and the heights of those peaks on the tilted angle of magnetic field are discussed.